Python 3.3.4 (v3.3.4:7ff62415e426, Feb 10 2014, 18:13:51) [MSC v.1600 64 bit (AMD64)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> 
>>> 'spam' + 'ni'
'spamni'
>>> 2 / 3
0.6666666666666666
>>> ================================ RESTART ================================
>>> 
C:\class
1267650600228229401496703205376
SpamSpamSpamSpamSpamSpamSpamSpam
>>> ================================ RESTART ================================
>>> 
C:\class
1267650600228229401496703205376
Traceback (most recent call last):
  File "C:\class\script1.py", line 5, in <module>
    x = 'Spam' + Y
NameError: name 'Y' is not defined
>>> ================================ RESTART ================================
>>> 
C:\class
1267650600228229401496703205376
SpamSpamSpamSpamSpamSpamSpamSpam
>>> 
>>> 
>>> import script1
C:\class
1267650600228229401496703205376
SpamSpamSpamSpamSpamSpamSpamSpam
>>> import script1
>>> import script1
>>> from imp import reload
>>> reload(script1)
C:\class
1267650600228229401496703205376
SpamSpamSpamSpamSpamSpamSpamSpam
<module 'script1' from 'C:\\class\\script1.py'>
>>> 
>>> exec(open('script1.py').read())
C:\class
1267650600228229401496703205376
SpamSpamSpamSpamSpamSpamSpamSpam
>>> 
>>> 
>>> x = 'spam'
>>> y = 32
>>> 
>>> x + y
Traceback (most recent call last):
  File "<pyshell#18>", line 1, in <module>
    x + y
TypeError: Can't convert 'int' object to str implicitly
>>> 
>>> x + str(y)
'spam32'
>>> 
>>> 
>>> 
>>> 
>>> S = 'spam'
>>> len(S)
4
>>> S + 'NI'
'spamNI'
>>> S * 8
'spamspamspamspamspamspamspamspam'
>>> 
>>> S[0]
's'
>>> S[1]
'p'
>>> S[-1]
'm'
>>> S[-2]
'a'
>>> S[len(S)-1]
'm'
>>> S
'spam'
>>> S[3]
'm'
>>> S[5]
Traceback (most recent call last):
  File "<pyshell#37>", line 1, in <module>
    S[5]
IndexError: string index out of range
>>> 
>>> S
'spam'
>>> S[1:3]
'pa'
>>> S[1:]
'pam'
>>> S[:3]
'spa'
>>> S[:-1]
'spa'
>>> S[:]
'spam'
>>> L = 'abcdefghujkl'
>>> L[::2]
'aceguk'
>>> L[1::2]
'bdfhjl'
>>> L
'abcdefghujkl'
>>> 
>>> L[::-1]
'lkjuhgfedcba'
>>> 
>>> 
>>> L
'abcdefghujkl'
>>> L.upper()
'ABCDEFGHUJKL'
>>> S
'spam'
>>> 
>>> S.replace('pa', '$!')
's$!m'
>>> 
>>> S
'spam'
>>> 
>>> X = S.replace('pa', '$!')
>>> X
's$!m'
>>> S
'spam'
>>> S[0] = '>'
Traceback (most recent call last):
  File "<pyshell#65>", line 1, in <module>
    S[0] = '>'
TypeError: 'str' object does not support item assignment
>>> 
>>> S = '>' + S[1:]
>>> S
'>pam'
>>> 
>>> dir(S)
['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
>>> 
>>> S
'>pam'
>>> S + 'NI'
'>pamNI'
>>> S.__add__('NI')
'>pamNI'
>>> help(S.rstrip)
Help on built-in function rstrip:

rstrip(...)
    S.rstrip([chars]) -> str
    
    Return a copy of the string S with trailing whitespace removed.
    If chars is given and not None, remove characters in chars instead.

>>> 
>>> 
>>> line = 'abcdefg\n'
>>> 
>>> line[:-1]
'abcdefg'
>>> 
>>> line.rstrip()
'abcdefg'
>>> 
>>> 
>>> line = '111,222,333,444\n'
>>> 
>>> line.split(',')
['111', '222', '333', '444\n']
>>> 
>>> line.rstrip().split(',')
['111', '222', '333', '444']
>>> 
>>> line.find('222')
4
>>> 
>>> '222' in line
True
>>> '2xx' in line
False
>>> 
>>> line[4]
'2'
>>> line[3]
','
>>> ord('\n')
10
>>> '222' in line
True
>>> line
'111,222,333,444\n'
>>> 
>>> cols = line.rstrip().split(',')
>>> line
'111,222,333,444\n'
>>> cols
['111', '222', '333', '444']
>>> cols[1]
'222'
>>> help(line.find)
Help on built-in function find:

find(...)
    S.find(sub[, start[, end]]) -> int
    
    Return the lowest index in S where substring sub is found,
    such that sub is contained within S[start:end].  Optional
    arguments start and end are interpreted as in slice notation.
    
    Return -1 on failure.

>>> line
'111,222,333,444\n'
>>> 
>>> file = line * 4
>>> file
'111,222,333,444\n111,222,333,444\n111,222,333,444\n111,222,333,444\n'
>>> lines = file.split('\n')
>>> lines
['111,222,333,444', '111,222,333,444', '111,222,333,444', '111,222,333,444', '']
>>> 
>>> file
'111,222,333,444\n111,222,333,444\n111,222,333,444\n111,222,333,444\n'
>>> 
>>> print(file)
111,222,333,444
111,222,333,444
111,222,333,444
111,222,333,444

>>> 
>>> 
>>> L = [123, 'spam', 3.14]
>>> L[0] = 789
>>> L
[789, 'spam', 3.14]
>>> len(L)
3
>>> L + [6, 7, 8]
[789, 'spam', 3.14, 6, 7, 8]
>>> L
[789, 'spam', 3.14]
>>> 
>>> L * 4
[789, 'spam', 3.14, 789, 'spam', 3.14, 789, 'spam', 3.14, 789, 'spam', 3.14]
>>> 
>>> L
[789, 'spam', 3.14]
>>> L[-1]
3.14
>>> L[1:]
['spam', 3.14]
>>> L
[789, 'spam', 3.14]
>>> 
>>> L.append('NI!')
>>> L
[789, 'spam', 3.14, 'NI!']
>>> L.index(3.14)
2
>>> L.remove('spam')
>>> L
[789, 3.14, 'NI!']
>>> L.insert(1, 'Spam')
>>> L
[789, 'Spam', 3.14, 'NI!']
>>> dir(L)
['__add__', '__class__', '__contains__', '__delattr__', '__delitem__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__iter__', '__le__', '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__reversed__', '__rmul__', '__setattr__', '__setitem__', '__sizeof__', '__str__', '__subclasshook__', 'append', 'clear', 'copy', 'count', 'extend', 'index', 'insert', 'pop', 'remove', 'reverse', 'sort']
>>> 
>>> help(L.insert)
Help on built-in function insert:

insert(...)
    L.insert(index, object) -- insert object before index

>>> 
>>> M = [
	[1, 2, 3],
	[4, 5, 6],
	[7, 8, 9]]
>>> 
>>> M[1]
[4, 5, 6]
>>> M[1][2]
6
>>> col2 = [row[1] for row in M]
>>> col2
[2, 5, 8]
>>> 
>>> diag  = [M[i][i] for i in [0, 1, 2]]
>>> diag
[1, 5, 9]
>>> 
>>> file
'111,222,333,444\n111,222,333,444\n111,222,333,444\n111,222,333,444\n'
>>> 
>>> lines
['111,222,333,444', '111,222,333,444', '111,222,333,444', '111,222,333,444', '']
>>> 
>>> file
'111,222,333,444\n111,222,333,444\n111,222,333,444\n111,222,333,444\n'
>>> 
>>> [line.split(',') for line in lines]
[['111', '222', '333', '444'], ['111', '222', '333', '444'], ['111', '222', '333', '444'], ['111', '222', '333', '444'], ['']]
>>> 
>>> 
>>> D = {'a': 1, 'b': 2, 'c': 3}
>>> D['b']
2
>>> D.keys()
dict_keys(['b', 'c', 'a'])
>>> D.values()
dict_values([2, 3, 1])
>>> 
>>> K = 'd'
>>> D[K] = 4
>>> D
{'b': 2, 'c': 3, 'a': 1, 'd': 4}
>>> 
>>> D['a'] = 0
>>> D
{'b': 2, 'c': 3, 'a': 0, 'd': 4}
>>> 
>>> D = {'a': 123, 'b': 'spam', 'c': 3.14}
>>> D
{'b': 'spam', 'c': 3.14, 'a': 123}
>>> D['a']
123
>>> D['c']
3.14
>>> 
>>> 
>>> 
>>> rec = {'name': {'first': 'Bob', 'last': 'Smith'},
           'age':  40.5,
           'job':  ['dev', 'mgr']}
>>> 
>>> rec['name']
{'first': 'Bob', 'last': 'Smith'}
>>> rec['name']['first']
'Bob'
>>> rec['job'][1]
'mgr'
>>> rec['job']
['dev', 'mgr']
>>> rec['job'].append('janitor')
>>> 
>>> rec
{'age': 40.5, 'name': {'first': 'Bob', 'last': 'Smith'}, 'job': ['dev', 'mgr', 'janitor']}
>>> 
>>> 
>>> rec.has_key('name')
Traceback (most recent call last):
  File "<pyshell#206>", line 1, in <module>
    rec.has_key('name')
AttributeError: 'dict' object has no attribute 'has_key'
>>> 
>>> 'name' in rec
True
>>> 
KeyboardInterrupt
>>> 
>>> 
>>> S = 'abcdefghij'
>>> S[3:1:-1]
'dc'
>>> 
>>> 
>>> 
>>> file = open('data.txt', 'w')
>>> file.write('Hello\n')
6
>>> file.write('world...\n')
9
>>> file.close()
>>> 
>>> file = open('data.txt', 'r')
>>> file.read()
'Hello\nworld...\n'
>>> 
>>> file = open('data.txt', 'r')
>>> text = file.read()
>>> text
'Hello\nworld...\n'
>>> print(text)
Hello
world...

>>> import csv
>>> 
>>> file = open('data.txt', 'w')
>>> file.write('111\t222\t333\n')
12
>>> file.write('444\t555\t666\n')
12
>>> file.close()
>>> 
>>> file = open('data.txt')
>>> print(file.read())
111	222	333
444	555	666

>>> 
>>> file = open('data.txt')
>>> data = file.read()
>>> data
'111\t222\t333\n444\t555\t666\n'
>>> lines = data.splitlines()
>>> lines
['111\t222\t333', '444\t555\t666']
>>> 
>>> cols = [line.split() for line in lines]
>>> cols
[['111', '222', '333'], ['444', '555', '666']]
>>> 
>>> S = '111'
>>> int(S)
111
>>> float(S)
111.0
>>> 
>>> S = {1, 2, 3, 4, 5}
>>> S
{1, 2, 3, 4, 5}
>>> T = {2, 4, 6}
>>> 
>>> S & T
{2, 4}
>>> S | T
{1, 2, 3, 4, 5, 6}
>>> 
>>> L = [1, 2, 1, 3, 4, 2, 1, 3, 3]
>>> set(L)
{1, 2, 3, 4}
>>> 

>>> list(set(L))
[1, 2, 3, 4]
>>> 
>>> 
>>> None
>>> 
>>> 
>>> L = [None] * 100
>>> L
[None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None]
>>> 
>>> 
>>> 'spam' + None
Traceback (most recent call last):
  File "<pyshell#272>", line 1, in <module>
    'spam' + None
TypeError: Can't convert 'NoneType' object to str implicitly
>>> 
>>> 
>>> 
>>> S = 'spam'
>>> S + ('' * (10 - len(S)))
'spam'
>>> S + (' ' * (10 - len(S)))
'spam      '
>>> 
>>> L
[None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None]
>>> 
>>> 
>>> L[0] = 0
>>> L
[0, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None]
>>> 
>>> L = [0] * 100
>>> L
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
>>> 
>>> None
>>> 
>>> L = [None] * 100
>>> L
[None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None, None]
>>> 
>>> 
>>> for i in range(100):
	L[i] = i

	
>>> L
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]
>>> 
>>> range(5)
range(0, 5)
>>> 
>>> list(range(5))
[0, 1, 2, 3, 4]
>>> 
>>> 
>>> for i in range(100):
	L[i] = float(i)

	
>>> L
[0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 23.0, 24.0, 25.0, 26.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 63.0, 64.0, 65.0, 66.0, 67.0, 68.0, 69.0, 70.0, 71.0, 72.0, 73.0, 74.0, 75.0, 76.0, 77.0, 78.0, 79.0, 80.0, 81.0, 82.0, 83.0, 84.0, 85.0, 86.0, 87.0, 88.0, 89.0, 90.0, 91.0, 92.0, 93.0, 94.0, 95.0, 96.0, 97.0, 98.0, 99.0]
>>> 
>>> 
>>> 
>>> 
>>> A = 4
>>> B = A
>>> 
>>> A = A + 1
>>> A
5
>>> B
4
>>> 
>>> A = [1, 2]
>>> B = A
>>> A[0] = 5
>>> A
[5, 2]
>>> B
[5, 2]
>>> 
>>> 
>>> 
>>> A = [1, 2]
>>> B = A[:]
>>> A
[1, 2]
>>> B
[1, 2]
>>> A[0] = 5
>>> A
[5, 2]
>>> B
[1, 2]
>>> 
>>> 
>>> 
>>> A = [1, 2]
>>> B = A
>>> 
>>> A == B
True
>>> A is B
True
>>> 
>>> A = [1, 2]
>>> B = A[:]
>>> 
>>> A == B
True
>>> A is B
False
>>> 
>>> 
>>> msg = """
aaaaaaaaaaaaa
bbbbbbbb'''bb""bbb
cccccccccccccc"""
>>> 
>>> msg
'\naaaaaaaaaaaaa\nbbbbbbbb\'\'\'bb""bbb\ncccccccccccccc'
>>> 
>>> 
>>> def func():
	"""
        stuff about func....
        """
KeyboardInterrupt
>>> 
>>> open(r'C:\new\text.dat') 
KeyboardInterrupt
>>> 
>>> 
>>> 
>>> 
>>> 
>>> X = 123
>>> Y = 'spam'
>>> Z = 1.2345
>>> 
>>> import struct
>>> data = struct.pack('<i4sf', X, Y, Z)
Traceback (most recent call last):
  File "<pyshell#373>", line 1, in <module>
    data = struct.pack('<i4sf', X, Y, Z)
struct.error: argument for 's' must be a bytes object
>>> 
>>> 
>>> 
>>> X = 123
>>> Y = b'spam'
>>> Z = 1.2345
>>> 
>>> import struct
>>> data = struct.pack('<i4sf', X, Y, Z)
>>> data
b'{\x00\x00\x00spam\x19\x04\x9e?'
>>> 
>>> file = open('data.bin', 'wb')
>>> file.write(data)
12
>>> file.close()
>>> 
>>> file = open('data.bin', 'rb')
>>> data = file.read()
>>> data
b'{\x00\x00\x00spam\x19\x04\x9e?'
>>> 
>>> vals = struct.unpack('<i4sf', data)
>>> vals
(123, b'spam', 1.2345000505447388)
>>> 
>>> 1.2345
1.2345
>>> vals[2]
1.2345000505447388
>>> 
>>> 
>>> 
>>> X = 123
>>> Y = b'spam'
>>> Z = 1.2345
>>> 
>>> import pickle
>>> str = pickle.dumps([X, Y, Z])
>>> str
b'\x80\x03]q\x00(K{C\x04spamq\x01G?\xf3\xc0\x83\x12n\x97\x8de.'
>>> 
>>> file = open('data.pkl', 'wb')
>>> file.write(str)
27
>>> file.close()
>>> 
>>> file = open('data.pkl', 'rb')
>>> data = file.read()
>>> data
b'\x80\x03]q\x00(K{C\x04spamq\x01G?\xf3\xc0\x83\x12n\x97\x8de.'
>>> 
>>> vals = pickle.loads(data)
>>> vals
[123, b'spam', 1.2345]
>>> help(pickle)
KeyboardInterrupt
>>> 
>>> 
>>> int('123')
123
>>> ================================ RESTART ================================
>>> 
enter age:50
2500
enter age:40
1600
enter age:30
900
enter age:20
400
enter age:stop
bye
>>> ================================ RESTART ================================
>>> 
enter age:99
9801
enter age:spam
Traceback (most recent call last):
  File "C:/class/interact.py", line 4, in <module>
    print(int(answer) ** 2)
ValueError: invalid literal for int() with base 10: 'spam'
>>> 
>>> x = 'spam'
>>> x.isdigit()
False
>>> x = '99'
>>> x.isdigit()
True
>>> ================================ RESTART ================================
>>> 
enter age:20
400
enter age:spam
Bad!
enter age:80
6400
enter age:stop
Bad!
enter age:
Traceback (most recent call last):
  File "C:/class/interact.py", line 2, in <module>
    answer = input('enter age:')
  File "C:\Python33\lib\idlelib\PyShell.py", line 1381, in readline
    line = self._line_buffer or self.shell.readline()
KeyboardInterrupt
>>> 
>>> ================================ RESTART ================================
>>> 
enter age:90
8100
enter age:spam
Bad!
enter age:stop
bye
>>> ================================ RESTART ================================
>>> 
enter age:80
6400
enter age:40.5
Bad!
enter age:stop
bye
>>> 123.99E+100
1.2399e+102
>>> 1.0
1.0
>>> ================================ RESTART ================================
>>> 
enter age:90
8100.0
enter age:1.23
1.5129
enter age:40.0
1600.0
enter age:123.45e+50
1.5239902500000003e+104
enter age:spam
Bad!
enter age:
Bad!
enter age:stop
bye
>>> ================================ RESTART ================================
>>> 
enter age:
Traceback (most recent call last):
  File "C:/class/interact.py", line 2, in <module>
    answer = input('enter age:')
  File "C:\Python33\lib\idlelib\PyShell.py", line 1381, in readline
    line = self._line_buffer or self.shell.readline()
KeyboardInterrupt
>>> ================================ RESTART ================================
>>> 
enter age:90
8100.0
enter age:
No...
8100.0
enter age:stop
bye
>>> file = open('data.bin', 'rb')
KeyboardInterrupt
>>> 
>>> 
>>> 
>>> X = [1, 2, 3, 4]
>>> X = 0
>>> 
>>> 
>>> X = [1, 2, 3, 4]
>>> Y = X
>>> X = 0
>>> Y
[1, 2, 3, 4]
>>> X = 3
>>> while X > 0:
	print(X)
	X = X -1

	
3
2
1
>>> while X > 0:
	print(X)
	X = X -1

	
>>> 
>>> X
0
>>> 
>>> T
Traceback (most recent call last):
  File "<pyshell#456>", line 1, in <module>
    T
NameError: name 'T' is not defined
>>> 
>>> T = T + 1
Traceback (most recent call last):
  File "<pyshell#458>", line 1, in <module>
    T = T + 1
NameError: name 'T' is not defined
>>> 
>>> T = S = 0
>>> T = T+1
>>> T
1
>>> S
0
>>> 
>>> T = S = []
>>> T.append(1)
>>> T
[1]
>>> S
[1]
>>> 
>>> T, S = [], []
>>> T.append(1)
>>> T
[1]
>>> S
[]
>>> a, b, c = [1, 2, 3]
>>> a
1
>>> b
2
>>> c
3
>>> 
>>> a, b = [1, 2, 3]
Traceback (most recent call last):
  File "<pyshell#479>", line 1, in <module>
    a, b = [1, 2, 3]
ValueError: too many values to unpack (expected 2)
>>> 
>>> a, *b = [1, 2, 3]
>>> a
1
>>> b
[2, 3]
>>> *a, b = [1, 2, 3]
>>> a
[1, 2]
>>> b
3
>>> a, *b, c = [1, 2, 3, 4]
>>> a
1
>>> b
[2, 3]
>>> c
4
>>> X
0
>>> X += 1
>>> X
1
>>> X = X + 1
>>> X
2
>>> X = 3
>>> while X > 0:
	print(X)
	X -= 1

	
3
2
1
>>> L = [1, 2]
>>> M = [3, 4]
>>> L += M
>>> L
[1, 2, 3, 4]
>>> L.extend(M)
>>> L
[1, 2, 3, 4, 3, 4]
>>> 
>>> 
>>> L = []
>>> L.append(22)
>>> L
[22]
>>> 
>>> L = L.append(33)
>>> print(L)
None
>>> L
>>> L = []
>>> print(L.append(44))
None
>>> L
[44]
>>> D = {'a': 1, 'b': 2, 'c': 3}
>>> D
{'a': 1, 'b': 2, 'c': 3}
>>> 
>>> D.keys()
dict_keys(['a', 'b', 'c'])
>>> 
>>> ks = D.keys()
>>> ks = list(ks)
>>> ks.sort()
>>> ks
['a', 'b', 'c']
>>> 
>>> ks = D.keys().sort() 
KeyboardInterrupt
>>> 
>>> 
>>> 
>>> D
{'a': 1, 'b': 2, 'c': 3}
>>> for key in D.keys():
	print(key, '=>', D[key])

	
a => 1
b => 2
c => 3
>>> ord('s')
115
>>> 
>>> L
[44]
>>> 
>>> 
>>> L.sort(reverse=True)
>>> 
>>> L.sort()
>>> L.reverse()
>>> 
>>> print L
SyntaxError: invalid syntax
>>> print(L)
[44]
>>> 
>>> 
>>> D
{'a': 1, 'b': 2, 'c': 3}
>>> 
>>> D.values()
dict_values([1, 2, 3])
>>> Vs = D.values()
>>> Vs = list(Vs)
>>> Vs.sort()
>>> Vs
[1, 2, 3]
>>> 
>>> L = [1, 'a', 3.14, 'b']
>>> L.sort()
Traceback (most recent call last):
  File "<pyshell#562>", line 1, in <module>
    L.sort()
TypeError: unorderable types: str() < int()
>>> 
>>> 
>>> 
>>> print(1, 2, 3)
1 2 3
>>> 
>>> print(1, 2, 3, sep='++')
1++2++3
>>> 
>>> print(1, 2, 3, sep='++', end='???')
1++2++3???
>>> print(1, 2, 3, sep='++', end='???'); print('more')
1++2++3???more
>>> 
>>> print(1, 2, 3, sep='++', file=open('output', 'w'))
>>> 
>>> open('output').read()
'1++2++3\n'
>>> print(1, 2, 3, sep='++', file=open('output', 'w'), flush=True)
>>> 
>>> print('%s = %e' % ('spam', 3.1415))
spam = 3.141500e+00
>>> 
>>> print('%s = %+.2e' % ('spam', 3.1415))
spam = +3.14e+00
>>> print('%s = %0.2e' % ('spam', 3.1415))
spam = 3.14e+00
>>> 
>>> print('%s = %010.2e' % ('spam', 3.1415))
spam = 003.14e+00
>>> 
>>> 
>>> import docstrings
>>> 
>>> docstrings.__doc__
'\nModule documentation\nWords Go Here\n'
>>> print(docstrings.__doc__)

Module documentation
Words Go Here

>>> print(docstrings.square.__doc__)

    function documentation
    can we have your liver then?
    
>>> print(docstrings.MyClass.__doc__)

    things about my class
    
>>> help(docstrings)
Help on module docstrings:

NAME
    docstrings

DESCRIPTION
    Module documentation
    Words Go Here

CLASSES
    builtins.object
        MyClass
    
    class MyClass(builtins.object)
     |  things about my class
     |  
     |  Data descriptors defined here:
     |  
     |  __dict__
     |      dictionary for instance variables (if defined)
     |  
     |  __weakref__
     |      list of weak references to the object (if defined)
     |  
     |  ----------------------------------------------------------------------
     |  Data and other attributes defined here:
     |  
     |  x = 1

FUNCTIONS
    square(x)
        function documentation
        can we have your liver then?

DATA
    spam = 40

FILE
    c:\class\docstrings.py


>>> 
>>> help(docstrings.square)
Help on function square in module docstrings:

square(x)
    function documentation
    can we have your liver then?

>>> ================================ RESTART ================================
>>> 
>>> ================================ RESTART ================================
>>> 
>>> 
>>> 
>>> x, y, z = 1, 2, 3
>>> 
>>> if x < y and y < z:
	print('yes')

	
yes
>>> if x < y or y > z:
	print('yes')

	
yes
>>> if x < y or not y > z:
	print('yes')

	
yes
>>> 
>>> if f1() or f2():  
KeyboardInterrupt
>>> 
>>> x = f1(); y = f2()
KeyboardInterrupt
>>> x ^ y
3
>>> 
>>> 
>>> 
>>> file = open('script1.py')
>>> file.readline()
'# a first script\n'
>>> file.readline()
'import os\n'
>>> file.readline()
'print(os.getcwd())\n'
>>> file.readline()
'print(2 ** 100)\n'
>>> file.readline()
"x = 'Spam'\n"
>>> file.readline()
'print(x * 8)\n'
>>> file.readline()
''
>>> 
>>> file = open('script1.py')
>>> file.__next__()
'# a first script\n'
>>> file.__next__()
'import os\n'
>>> file.__next__()
'print(os.getcwd())\n'
>>> file.__next__()
'print(2 ** 100)\n'
>>> file.__next__()
"x = 'Spam'\n"
>>> file.__next__()
'print(x * 8)\n'
>>> file.__next__()
Traceback (most recent call last):
  File "<pyshell#630>", line 1, in <module>
    file.__next__()
StopIteration
>>> 
>>> 
>>> for line in open('script1.py'):
	print(line.upper(), end='')

	
# A FIRST SCRIPT
IMPORT OS
PRINT(OS.GETCWD())
PRINT(2 ** 100)
X = 'SPAM'
PRINT(X * 8)
>>> 
>>> for line in open('script1.py').readlines():
	print(line.upper(), end='')
KeyboardInterrupt
>>> 
>>> 
>>> res = [line.rstrip() for line in open('script1.py')]
>>> res
['# a first script', 'import os', 'print(os.getcwd())', 'print(2 ** 100)', "x = 'Spam'", 'print(x * 8)']
>>> 
>>> res = []
>>> for line in open('script1.py'):
	res.append(line.rstrip())
	
	
>>> res
['# a first script', 'import os', 'print(os.getcwd())', 'print(2 ** 100)', "x = 'Spam'", 'print(x * 8)']
>>> 
>>> res = [line.rstrip() for line in open('script1.py') if line[0] == 'p']
>>> res
['print(os.getcwd())', 'print(2 ** 100)', 'print(x * 8)']
>>> 
>>> res = []
>>> for line in open('script1.py'):
	if line[0] == 'p':
	    res.append(line.rstrip())

	    
>>> res
['print(os.getcwd())', 'print(2 ** 100)', 'print(x * 8)']
>>> 
>>> [x + y for x in 'abc' for y in 'lmn']
['al', 'am', 'an', 'bl', 'bm', 'bn', 'cl', 'cm', 'cn']
>>> 
>>> res = []
>>> for x in 'abc':
	for y in 'lmn':
		res.append(x + y)

		
>>> res
['al', 'am', 'an', 'bl', 'bm', 'bn', 'cl', 'cm', 'cn']
>>> 
>>> map(ord, 'spam')
<map object at 0x0000000003325BE0>
>>> list(map(ord, 'spam'))
[115, 112, 97, 109]
>>> 
>>> M = map(ord, 'spam')
>>> M
<map object at 0x0000000003325F98>
>>> 
>>> M.__next__()
115
>>> M.__next__()
112
>>> M.__next__()
97
>>> M.__next__()
109
>>> M.__next__()
Traceback (most recent call last):
  File "<pyshell#676>", line 1, in <module>
    M.__next__()
StopIteration
>>> 
>>> for c in map(ord, 'spam'): print(c ** 2)

13225
12544
9409
11881
>>> M = map(ord, 'spam')
>>> next(M)
115
>>> next(M)
112
>>> next(M)
97
>>> next(M)
109
>>> next(M)
Traceback (most recent call last):
  File "<pyshell#685>", line 1, in <module>
    next(M)
StopIteration
>>> 
>>> map(ord, 'spam')
<map object at 0x0000000003325DA0>
>>> 
>>> list(map(ord, 'spam'))
[115, 112, 97, 109]
>>> 
>>> [ord(c) for c in 'spam']
[115, 112, 97, 109]
>>> 
>>> 
>>> [x ** 2 for x in [1, 2, 3, 4]]
[1, 4, 9, 16]
>>> 
>>> 
>>> def f(X): return X ** 2

>>> list(map(f, [1, 2, 3, 4]))
[1, 4, 9, 16]
>>> [x ** 2 for x in [1, 2, 3, 4]]
[1, 4, 9, 16]
>>> 
>>> 
>>> D
Traceback (most recent call last):
  File "<pyshell#704>", line 1, in <module>
    D
NameError: name 'D' is not defined
>>> 
>>> D = dict(a=1, b=2, c=3)
>>> D
{'b': 2, 'c': 3, 'a': 1}
>>> 
>>> for key in D:
	print(key, D[key])

	
b 2
c 3
a 1
>>> D
{'b': 2, 'c': 3, 'a': 1}
>>> D.__next__()
Traceback (most recent call last):
  File "<pyshell#713>", line 1, in <module>
    D.__next__()
AttributeError: 'dict' object has no attribute '__next__'
>>> 
>>> I = iter(D)
>>> I.__next__()
'b'
>>> I.__next__()
'c'
>>> I.__next__()
'a'
>>> I.__next__()
Traceback (most recent call last):
  File "<pyshell#719>", line 1, in <module>
    I.__next__()
StopIteration
>>> 
>>> 
>>> L = [x ** 2 for x in [1, 2, 3, 4]]
>>> L
[1, 4, 9, 16]
>>> 
>>> L = (x ** 2 for x in [1, 2, 3, 4])
>>> L
<generator object <genexpr> at 0x0000000003350B88>
>>> 
>>> I = iter(L)
>>> I.__next__()
1
>>> I.__next__()
4
>>> I.__next__()
9
>>> I.__next__()
16
>>> I.__next__()
Traceback (most recent call last):
  File "<pyshell#733>", line 1, in <module>
    I.__next__()
StopIteration
>>> 
>>> for n in (x ** 2 for  x in [1, 2, 3, 4]):
	print(n * 10)

	
10
40
90
160
>>> 
>>> {ord(c) for c in 'sppaaaammmmmm'}
{112, 97, 115, 109}
>>> 
>>> {c: ord(c) for c in 'sppaaammmmm'}
{'s': 115, 'p': 112, 'a': 97, 'm': 109}
>>> 
>>> range(50)
range(0, 50)
>>> list(range(50))
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49]
>>> 
>>> 
>>> L = [1, 2, 3, 4, 5]
>>> 
>>> for x in L:
	x += 10

	
>>> x
15
>>> L
[1, 2, 3, 4, 5]
>>> 
>>> L = [1, 2, 3, 4, 5]
>>> for i in range(len(L)):
	L[i] += 10

	
>>> L
[11, 12, 13, 14, 15]
>>> 
>>> 
>>> L
[11, 12, 13, 14, 15]
>>> E = enumerate(L)
>>> 
>>> E.__next__()
(0, 11)
>>> E.__next__()
(1, 12)
>>> E.__next__()
(2, 13)
>>> E.__next__()
(3, 14)
>>> E.__next__()
(4, 15)
>>> E.__next__()
Traceback (most recent call last):
  File "<pyshell#769>", line 1, in <module>
    E.__next__()
StopIteration
>>> 
>>> 
>>> 
>>> 
>>> list(zip('abc', 'def', 'ghi', 'jkl'))
[('a', 'd', 'g', 'j'), ('b', 'e', 'h', 'k'), ('c', 'f', 'i', 'l')]
>>> 
>>> list(zip('abc', 'def', 'ghi', 'jklxxx'))
[('a', 'd', 'g', 'j'), ('b', 'e', 'h', 'k'), ('c', 'f', 'i', 'l')]
>>> 
>>> 
>>> [x ** 2 for x in range(5)]
[0, 1, 4, 9, 16]
>>> list((x ** 2 for x in range(5)))
[0, 1, 4, 9, 16]
>>> {x ** 2 for x in range(5)}
{0, 1, 4, 16, 9}
>>> {x: x ** 2 for x in range(5)}
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
>>> 
>>> [ord(c) for c in 'spam']
[115, 112, 97, 109]
>>> list((ord(c) for c in 'spam'))
[115, 112, 97, 109]
>>> {ord(c) for c in 'spam'}
{112, 97, 115, 109}
>>> {c: ord(c) for c in 'spam'}
{'s': 115, 'p': 112, 'a': 97, 'm': 109}
>>> ================================ RESTART ================================
>>> 
66
66
>>> ================================ RESTART ================================
>>> 
66
66
>>> ================================ RESTART ================================
>>> 
77
66
>>> ================================ RESTART ================================
>>> 
77
77
>>> len = 99
>>> len
99
>>> del len
>>> len
<built-in function len>
>>> 
>>> import builtins
>>> dir(builtins)
['ArithmeticError', 'AssertionError', 'AttributeError', 'BaseException', 'BlockingIOError', 'BrokenPipeError', 'BufferError', 'BytesWarning', 'ChildProcessError', 'ConnectionAbortedError', 'ConnectionError', 'ConnectionRefusedError', 'ConnectionResetError', 'DeprecationWarning', 'EOFError', 'Ellipsis', 'EnvironmentError', 'Exception', 'False', 'FileExistsError', 'FileNotFoundError', 'FloatingPointError', 'FutureWarning', 'GeneratorExit', 'IOError', 'ImportError', 'ImportWarning', 'IndentationError', 'IndexError', 'InterruptedError', 'IsADirectoryError', 'KeyError', 'KeyboardInterrupt', 'LookupError', 'MemoryError', 'NameError', 'None', 'NotADirectoryError', 'NotImplemented', 'NotImplementedError', 'OSError', 'OverflowError', 'PendingDeprecationWarning', 'PermissionError', 'ProcessLookupError', 'ReferenceError', 'ResourceWarning', 'RuntimeError', 'RuntimeWarning', 'StopIteration', 'SyntaxError', 'SyntaxWarning', 'SystemError', 'SystemExit', 'TabError', 'TimeoutError', 'True', 'TypeError', 'UnboundLocalError', 'UnicodeDecodeError', 'UnicodeEncodeError', 'UnicodeError', 'UnicodeTranslateError', 'UnicodeWarning', 'UserWarning', 'ValueError', 'Warning', 'WindowsError', 'ZeroDivisionError', '_', '__build_class__', '__debug__', '__doc__', '__import__', '__loader__', '__name__', '__package__', 'abs', 'all', 'any', 'ascii', 'bin', 'bool', 'bytearray', 'bytes', 'callable', 'chr', 'classmethod', 'compile', 'complex', 'copyright', 'credits', 'delattr', 'dict', 'dir', 'divmod', 'enumerate', 'eval', 'exec', 'exit', 'filter', 'float', 'format', 'frozenset', 'getattr', 'globals', 'hasattr', 'hash', 'help', 'hex', 'id', 'input', 'int', 'isinstance', 'issubclass', 'iter', 'len', 'license', 'list', 'locals', 'map', 'max', 'memoryview', 'min', 'next', 'object', 'oct', 'open', 'ord', 'pow', 'print', 'property', 'quit', 'range', 'repr', 'reversed', 'round', 'set', 'setattr', 'slice', 'sorted', 'staticmethod', 'str', 'sum', 'super', 'tuple', 'type', 'vars', 'zip']
>>> True = False
SyntaxError: assignment to keyword
>>> def open(...):
	
SyntaxError: invalid syntax
>>> 
>>> def open(args): ...

>>> builtins.open = open
KeyboardInterrupt
>>> 
>>> 
>>> 
>>> def maker(N):
	def action(X):
		return X ** N
	return action

>>> f = maker(3)
>>> f
<function maker.<locals>.action at 0x00000000034BA488>
>>> 
>>> f(2)
8
>>> g = maker(4)
>>> g
<function maker.<locals>.action at 0x00000000034BA510>
>>> g(2)
16
>>> 
>>> f(2)
8
>>> h = maker(100)
>>> h(2)
1267650600228229401496703205376
>>> 
>>> f(2)
8
>>> g(2)
16
>>> f(3)
27
>>> h(3)
515377520732011331036461129765621272702107522001
>>> 
>>> import dis
>>> dir(h)
['__annotations__', '__call__', '__class__', '__closure__', '__code__', '__defaults__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__get__', '__getattribute__', '__globals__', '__gt__', '__hash__', '__init__', '__kwdefaults__', '__le__', '__lt__', '__module__', '__name__', '__ne__', '__new__', '__qualname__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']
>>> 
>>> changer(X, L[:])  
KeyboardInterrupt
>>> 
>>> 
>>> 
>>> def f(a, *pargs, **kargs): print(a, pargs, kargs)

>>> f(1)
1 () {}
>>> f(1, 2, 3, 4)
1 (2, 3, 4) {}
>>> f(1, a=1, b=2, c=3, d=4)
Traceback (most recent call last):
  File "<pyshell#837>", line 1, in <module>
    f(1, a=1, b=2, c=3, d=4)
TypeError: f() got multiple values for argument 'a'
>>> 
>>> f(1, b=2, c=3, d=4)
1 () {'d': 4, 'b': 2, 'c': 3}
>>> 
>>> f(1, b=2, c=3, d=4, 9)
SyntaxError: non-keyword arg after keyword arg
>>> f(b=2, c=3, d=4)
Traceback (most recent call last):
  File "<pyshell#842>", line 1, in <module>
    f(b=2, c=3, d=4)
TypeError: f() missing 1 required positional argument: 'a'
>>> 
>>> f(a=1, b=2, c=3, d=4)
1 () {'d': 4, 'b': 2, 'c': 3}
>>> 
>>> f(1, 2, 3, 4)
1 (2, 3, 4) {}
>>> 
>>> 
>>> 
>>> def min(*args):
	low = args[0]
	for arg in args[1:]:
		if arg < low:
			low = arg
	return low

>>> min(1, 4, 3, 2, 5, 6)
1
>>> min('bb', 'aa', 'dd', 'cc')
'aa'
>>> 
>>> sum([1, 3, 2, 4, 5])
15
>>> 15
15

>>> 
>>> 
>>> 
>>> 
>>> M = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
>>> sum(sum(row) for row in M)
45
>>> ================================ RESTART ================================
>>> 
6
>>> ================================ RESTART ================================
>>> 
6
>>> import func1
>>> func1.f(4)
8
>>> 6
6

>>> 
>>> S = 'spam'
>>> S + 'NI'
'spamNI'
>>> S.__add__('NI')
'spamNI'
>>> 
>>> fname = 'script1.py'
>>> len(open(fname).read())
86
>>> len(open(fname).readlines())
6
>>> 
>>> tot = 0
>>> for line in open(fname): tot += 1

>>> tot
6
>>> 
>>> import os
>>> os.chdir(r'C:\somedir') 
KeyboardInterrupt
>>> 
>>> 
>>> import docstrings
>>> dir(docstrings)
['MyClass', '__builtins__', '__cached__', '__doc__', '__file__', '__initializing__', '__loader__', '__name__', '__package__', 'spam', 'square']
>>> 
>>> docstrings.__dict__.keys()
dict_keys(['__loader__', '__doc__', '__file__', 'spam', '__builtins__', '__initializing__', '__package__', '__name__', 'square', '__cached__', 'MyClass'])
>>> 
>>> docstrings.__dict__
>>> 
>>> 
>>> 
>>> 
>>> ================================ RESTART ================================
>>> 
Bob Smith Sue Jones 100000
>>> name = 'Bob Smith'
>>> name.split()
['Bob', 'Smith']
>>> name.split()[-1]
'Smith'
>>> ================================ RESTART ================================
>>> 
Bob Smith Sue Jones 100000
Smith
110000.00000000001
>>> ================================ RESTART ================================
>>> 
Bob Smith Sue Jones 100000
Smith
110000
>>> ================================ RESTART ================================
>>> 
Bob Smith Sue Jones 100000
Smith Jones
110000
>>> ================================ RESTART ================================
>>> 
Bob Smith Sue Jones 100000
Smith Jones
110000
<__main__.Person object at 0x000000000342D390>
>>> ================================ RESTART ================================
>>> 
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 100000.00]
Smith Jones
[Person: Sue Jones, 110000.00]
>>> ================================ RESTART ================================
>>> 
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 100000.00]
Smith Jones
[Person: Sue Jones, 110000.00]
[Person: Tom Jones, 50000.00]
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 121000.00]
[Person: Tom Jones, 60000.00]
>>> ================================ RESTART ================================
>>> 
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 100000.00]
Smith Jones
[Person: Sue Jones, 110000.00]
[Person: Tom Jones, 50000.00]
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 121000.00]
[Person: Tom Jones, 60000.00]
>>> ================================ RESTART ================================
>>> 
>>> import os
>>> os.listdir('.')
['data.bin', 'data.pkl', 'data.txt', 'docstrings.py', 'func1.py', 'interact.py', 'ksc.db.bak', 'ksc.db.dat', 'ksc.db.dir', 'makedb.py', 'output', 'person.py', 'prior', 'scopes.py', 'script1.py', 'stub.py', '__pycache__']
>>> ================================ RESTART ================================
>>> 
sue => [Person: Sue Jones, 100000.00]
bob => [Person: Bob Smith, 0.00]
tom => [Person: Tom Jones, 50000.00]
Smith None
>>> ================================ RESTART ================================
>>> 
tom => [Person: Tom Jones, 50000.00]
sue => [Person: Sue Jones, 110000.00]
bob => [Person: Bob Smith, 0.00]
Smith None
>>> ================================ RESTART ================================
>>> 
sue => [Person: Sue Jones, 121000.00]
tom => [Person: Tom Jones, 50000.00]
bob => [Person: Bob Smith, 0.00]
Smith None
>>> ================================ RESTART ================================
>>> 
bob => [Person: Bob Smith, 0.00]
sue => [Person: Sue Jones, 133100.00]
tom => [Person: Tom Jones, 50000.00]
Smith None
>>> ================================ RESTART ================================
>>> 
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 100000.00]
Smith Jones
[Person: Sue Jones, 110000.00]
[Person: Tom Jones, 50000.00]
[Person: Bob Smith, 0.00]
[Person: Sue Jones, 121000.00]
[Person: Tom Jones, 60000.00]
>>> 
>>> 
>>> from imp import reload
>>> reload(docstrings)
Traceback (most recent call last):
  File "<pyshell#910>", line 1, in <module>
    reload(docstrings)
NameError: name 'docstrings' is not defined
>>> 
>>> import docstrings
>>> 
>>> from imp import reload
>>> reload(docstrings)
<module 'docstrings' from 'C:/class\\docstrings.py'>
>>> 
>>> 
>>> 
>>> import this
The Zen of Python, by Tim Peters

Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
Flat is better than nested.
Sparse is better than dense.
Readability counts.
Special cases aren't special enough to break the rules.
Although practicality beats purity.
Errors should never pass silently.
Unless explicitly silenced.
In the face of ambiguity, refuse the temptation to guess.
There should be one-- and preferably only one --obvious way to do it.
Although that way may not be obvious at first unless you're Dutch.
Now is better than never.
Although never is often better than *right* now.
If the implementation is hard to explain, it's a bad idea.
If the implementation is easy to explain, it may be a good idea.
Namespaces are one honking great idea -- let's do more of those!
>>> 
>>> 
>>> import os
>>> dir(os)
...
>>> 
>>> len(dir(os))
145
>>> import sys
>>> dir(sys)
...
>>>