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
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
"""Add things to old Pythons so I can pretend they are newer."""
# This file does lots of tricky stuff, so disable a bunch of lintisms.
# pylint: disable=F0401,W0611,W0622
# F0401: Unable to import blah
# W0611: Unused import blah
# W0622: Redefining built-in blah
import os, re, sys
# Python 2.3 doesn't have `set`
try:
set = set # new in 2.4
except NameError:
from sets import Set as set
# Python 2.3 doesn't have `sorted`.
try:
sorted = sorted
except NameError:
def sorted(iterable):
"""A 2.3-compatible implementation of `sorted`."""
lst = list(iterable)
lst.sort()
return lst
# rpartition is new in 2.5
try:
"".rpartition
except AttributeError:
def rpartition(s, sep):
"""Implement s.rpartition(sep) for old Pythons."""
i = s.rfind(sep)
if i == -1:
return ('', '', s)
else:
return (s[:i], sep, s[i+len(sep):])
else:
def rpartition(s, sep):
"""A common interface for new Pythons."""
return s.rpartition(sep)
# Pythons 2 and 3 differ on where to get StringIO
try:
from cStringIO import StringIO
BytesIO = StringIO
except ImportError:
from io import StringIO, BytesIO
# What's a string called?
try:
string_class = basestring
except NameError:
string_class = str
# Where do pickles come from?
try:
import cPickle as pickle
except ImportError:
import pickle
# range or xrange?
try:
range = xrange
except NameError:
range = range
# A function to iterate listlessly over a dict's items.
if "iteritems" in dir({}):
def iitems(d):
"""Produce the items from dict `d`."""
return d.iteritems()
else:
def iitems(d):
"""Produce the items from dict `d`."""
return d.items()
# Exec is a statement in Py2, a function in Py3
if sys.version_info >= (3, 0):
def exec_code_object(code, global_map):
"""A wrapper around exec()."""
exec(code, global_map)
else:
# OK, this is pretty gross. In Py2, exec was a statement, but that will
# be a syntax error if we try to put it in a Py3 file, even if it is never
# executed. So hide it inside an evaluated string literal instead.
eval(
compile(
"def exec_code_object(code, global_map):\n"
" exec code in global_map\n",
"<exec_function>", "exec"
)
)
# Reading Python source and interpreting the coding comment is a big deal.
if sys.version_info >= (3, 0):
# Python 3.2 provides `tokenize.open`, the best way to open source files.
import tokenize
try:
open_source = tokenize.open # pylint: disable=E1101
except AttributeError:
from io import TextIOWrapper
detect_encoding = tokenize.detect_encoding # pylint: disable=E1101
# Copied from the 3.2 stdlib:
def open_source(fname):
"""Open a file in read only mode using the encoding detected by
detect_encoding().
"""
buffer = open(fname, 'rb')
encoding, _ = detect_encoding(buffer.readline)
buffer.seek(0)
text = TextIOWrapper(buffer, encoding, line_buffering=True)
text.mode = 'r'
return text
else:
def open_source(fname):
"""Open a source file the best way."""
return open(fname, "rU")
# Python 3.x is picky about bytes and strings, so provide methods to
# get them right, and make them no-ops in 2.x
if sys.version_info >= (3, 0):
def to_bytes(s):
"""Convert string `s` to bytes."""
return s.encode('utf8')
def to_string(b):
"""Convert bytes `b` to a string."""
return b.decode('utf8')
else:
def to_bytes(s):
"""Convert string `s` to bytes (no-op in 2.x)."""
return s
def to_string(b):
"""Convert bytes `b` to a string (no-op in 2.x)."""
return b
# Md5 is available in different places.
try:
import hashlib
md5 = hashlib.md5
except ImportError:
import md5
md5 = md5.new
|
