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"""
Miscellaneous function (re)definitions from the Py3.4+ standard library
for Python 2.6/2.7.
- math.ceil (for Python 2.7)
- collections.OrderedDict (for Python 2.6)
- collections.Counter (for Python 2.6)
- collections.ChainMap (for all versions prior to Python 3.3)
- itertools.count (for Python 2.6, with step parameter)
- subprocess.check_output (for Python 2.6)
- reprlib.recursive_repr (for Python 2.6+)
- functools.cmp_to_key (for Python 2.6)
"""
from __future__ import absolute_import
import subprocess
from math import ceil as oldceil
from operator import itemgetter as _itemgetter, eq as _eq
import sys
import heapq as _heapq
from _weakref import proxy as _proxy
from itertools import repeat as _repeat, chain as _chain, starmap as
_starmap
from socket import getaddrinfo, SOCK_STREAM, error, socket
from future.utils import iteritems, itervalues, PY2, PY26, PY3
if PY2:
from collections import Mapping, MutableMapping
else:
from collections.abc import Mapping, MutableMapping
def ceil(x):
"""
Return the ceiling of x as an int.
This is the smallest integral value >= x.
"""
return int(oldceil(x))
########################################################################
### reprlib.recursive_repr decorator from Py3.4
########################################################################
from itertools import islice
if PY3:
try:
from _thread import get_ident
except ImportError:
from _dummy_thread import get_ident
else:
try:
from thread import get_ident
except ImportError:
from dummy_thread import get_ident
def recursive_repr(fillvalue='...'):
'Decorator to make a repr function return fillvalue for a
recursive call'
def decorating_function(user_function):
repr_running = set()
def wrapper(self):
key = id(self), get_ident()
if key in repr_running:
return fillvalue
repr_running.add(key)
try:
result = user_function(self)
finally:
repr_running.discard(key)
return result
# Can't use functools.wraps() here because of bootstrap issues
wrapper.__module__ = getattr(user_function, '__module__')
wrapper.__doc__ = getattr(user_function, '__doc__')
wrapper.__name__ = getattr(user_function, '__name__')
wrapper.__annotations__ = getattr(user_function,
'__annotations__', {})
return wrapper
return decorating_function
################################################################################
### OrderedDict
################################################################################
class _Link(object):
__slots__ = 'prev', 'next', 'key',
'__weakref__'
class OrderedDict(dict):
'Dictionary that remembers insertion order'
# An inherited dict maps keys to values.
# The inherited dict provides __getitem__, __len__, __contains__, and
get.
# The remaining methods are order-aware.
# Big-O running times for all methods are the same as regular
dictionaries.
# The internal self.__map dict maps keys to links in a doubly linked
list.
# The circular doubly linked list starts and ends with a sentinel
element.
# The sentinel element never gets deleted (this simplifies the
algorithm).
# The sentinel is in self.__hardroot with a weakref proxy in
self.__root.
# The prev links are weakref proxies (to prevent circular references).
# Individual links are kept alive by the hard reference in self.__map.
# Those hard references disappear when a key is deleted from an
OrderedDict.
def __init__(*args, **kwds):
'''Initialize an ordered dictionary. The signature
is the same as
regular dictionaries, but keyword arguments are not recommended
because
their insertion order is arbitrary.
'''
if not args:
raise TypeError("descriptor '__init__' of
'OrderedDict' object "
"needs an argument")
self = args[0]
args = args[1:]
if len(args) > 1:
raise TypeError('expected at most 1 arguments, got
%d' % len(args))
try:
self.__root
except AttributeError:
self.__hardroot = _Link()
self.__root = root = _proxy(self.__hardroot)
root.prev = root.next = root
self.__map = {}
self.__update(*args, **kwds)
def __setitem__(self, key, value,
dict_setitem=dict.__setitem__, proxy=_proxy,
Link=_Link):
'od.__setitem__(i, y) <==> od[i]=y'
# Setting a new item creates a new link at the end of the linked
list,
# and the inherited dictionary is updated with the new key/value
pair.
if key not in self:
self.__map[key] = link = Link()
root = self.__root
last = root.prev
link.prev, link.next, link.key = last, root, key
last.next = link
root.prev = proxy(link)
dict_setitem(self, key, value)
def __delitem__(self, key, dict_delitem=dict.__delitem__):
'od.__delitem__(y) <==> del od[y]'
# Deleting an existing item uses self.__map to find the link which
gets
# removed by updating the links in the predecessor and successor
nodes.
dict_delitem(self, key)
link = self.__map.pop(key)
link_prev = link.prev
link_next = link.next
link_prev.next = link_next
link_next.prev = link_prev
def __iter__(self):
'od.__iter__() <==> iter(od)'
# Traverse the linked list in order.
root = self.__root
curr = root.next
while curr is not root:
yield curr.key
curr = curr.next
def __reversed__(self):
'od.__reversed__() <==> reversed(od)'
# Traverse the linked list in reverse order.
root = self.__root
curr = root.prev
while curr is not root:
yield curr.key
curr = curr.prev
def clear(self):
'od.clear() -> None. Remove all items from od.'
root = self.__root
root.prev = root.next = root
self.__map.clear()
dict.clear(self)
def popitem(self, last=True):
'''od.popitem() -> (k, v), return and remove a
(key, value) pair.
Pairs are returned in LIFO order if last is true or FIFO order if
false.
'''
if not self:
raise KeyError('dictionary is empty')
root = self.__root
if last:
link = root.prev
link_prev = link.prev
link_prev.next = root
root.prev = link_prev
else:
link = root.next
link_next = link.next
root.next = link_next
link_next.prev = root
key = link.key
del self.__map[key]
value = dict.pop(self, key)
return key, value
def move_to_end(self, key, last=True):
'''Move an existing element to the end (or beginning
if last==False).
Raises KeyError if the element does not exist.
When last=True, acts like a fast version of
self[key]=self.pop(key).
'''
link = self.__map[key]
link_prev = link.prev
link_next = link.next
link_prev.next = link_next
link_next.prev = link_prev
root = self.__root
if last:
last = root.prev
link.prev = last
link.next = root
last.next = root.prev = link
else:
first = root.next
link.prev = root
link.next = first
root.next = first.prev = link
def __sizeof__(self):
sizeof = sys.getsizeof
n = len(self) + 1 # number of links including
root
size = sizeof(self.__dict__) # instance dictionary
size += sizeof(self.__map) * 2 # internal dict and
inherited dict
size += sizeof(self.__hardroot) * n # link objects
size += sizeof(self.__root) * n # proxy objects
return size
update = __update = MutableMapping.update
keys = MutableMapping.keys
values = MutableMapping.values
items = MutableMapping.items
__ne__ = MutableMapping.__ne__
__marker = object()
def pop(self, key, default=__marker):
'''od.pop(k[,d]) -> v, remove specified key and
return the corresponding
value. If key is not found, d is returned if given, otherwise
KeyError
is raised.
'''
if key in self:
result = self[key]
del self[key]
return result
if default is self.__marker:
raise KeyError(key)
return default
def setdefault(self, key, default=None):
'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k
not in od'
if key in self:
return self[key]
self[key] = default
return default
@recursive_repr()
def __repr__(self):
'od.__repr__() <==> repr(od)'
if not self:
return '%s()' % (self.__class__.__name__,)
return '%s(%r)' % (self.__class__.__name__,
list(self.items()))
def __reduce__(self):
'Return state information for pickling'
inst_dict = vars(self).copy()
for k in vars(OrderedDict()):
inst_dict.pop(k, None)
return self.__class__, (), inst_dict or None, None,
iter(self.items())
def copy(self):
'od.copy() -> a shallow copy of od'
return self.__class__(self)
@classmethod
def fromkeys(cls, iterable, value=None):
'''OD.fromkeys(S[, v]) -> New ordered dictionary
with keys from S.
If not specified, the value defaults to None.
'''
self = cls()
for key in iterable:
self[key] = value
return self
def __eq__(self, other):
'''od.__eq__(y) <==> od==y. Comparison to
another OD is order-sensitive
while comparison to a regular mapping is order-insensitive.
'''
if isinstance(other, OrderedDict):
return dict.__eq__(self, other) and all(map(_eq, self, other))
return dict.__eq__(self, other)
# {{{ http://code.activestate.com/recipes/576611/ (r11)
try:
from operator import itemgetter
from heapq import nlargest
except ImportError:
pass
########################################################################
### Counter
########################################################################
def _count_elements(mapping, iterable):
'Tally elements from the iterable.'
mapping_get = mapping.get
for elem in iterable:
mapping[elem] = mapping_get(elem, 0) + 1
class Counter(dict):
'''Dict subclass for counting hashable items. Sometimes
called a bag
or multiset. Elements are stored as dictionary keys and their counts
are stored as dictionary values.
>>> c = Counter('abcdeabcdabcaba') # count elements
from a string
>>> c.most_common(3) # three most common
elements
[('a', 5), ('b', 4), ('c', 3)]
>>> sorted(c) # list all unique elements
['a', 'b', 'c', 'd',
'e']
>>> ''.join(sorted(c.elements())) # list elements
with repetitions
'aaaaabbbbcccdde'
>>> sum(c.values()) # total of all counts
15
>>> c['a'] # count of
letter 'a'
5
>>> for elem in 'shazam': # update counts
from an iterable
... c[elem] += 1 # by adding 1 to each
element's count
>>> c['a'] # now there are
seven 'a'
7
>>> del c['b'] # remove all
'b'
>>> c['b'] # now there are
zero 'b'
0
>>> d = Counter('simsalabim') # make another
counter
>>> c.update(d) # add in the second
counter
>>> c['a'] # now there are
nine 'a'
9
>>> c.clear() # empty the counter
>>> c
Counter()
Note: If a count is set to zero or reduced to zero, it will remain
in the counter until the entry is deleted or the counter is cleared:
>>> c = Counter('aaabbc')
>>> c['b'] -= 2 # reduce the
count of 'b' by two
>>> c.most_common() # 'b' is still
in, but its count is zero
[('a', 3), ('c', 1), ('b', 0)]
'''
# References:
# http://en.wikipedia.org/wiki/Multiset
#
http://www.gnu.org/software/smalltalk/manual-base/html_node/Bag.html
#
http://www.demo2s.com/Tutorial/Cpp/0380__set-multiset/Catalog0380__set-multiset.htm
# http://code.activestate.com/recipes/259174/
# Knuth, TAOCP Vol. II section 4.6.3
def __init__(*args, **kwds):
'''Create a new, empty Counter object. And if
given, count elements
from an input iterable. Or, initialize the count from another
mapping
of elements to their counts.
>>> c = Counter() # a new, empty
counter
>>> c = Counter('gallahad') # a
new counter from an iterable
>>> c = Counter({'a': 4, 'b': 2})
# a new counter from a mapping
>>> c = Counter(a=4, b=2) # a new
counter from keyword args
'''
if not args:
raise TypeError("descriptor '__init__' of
'Counter' object "
"needs an argument")
self = args[0]
args = args[1:]
if len(args) > 1:
raise TypeError('expected at most 1 arguments, got
%d' % len(args))
super(Counter, self).__init__()
self.update(*args, **kwds)
def __missing__(self, key):
'The count of elements not in the Counter is zero.'
# Needed so that self[missing_item] does not raise KeyError
return 0
def most_common(self, n=None):
'''List the n most common elements and their counts
from the most
common to the least. If n is None, then list all element counts.
>>> Counter('abcdeabcdabcaba').most_common(3)
[('a', 5), ('b', 4), ('c', 3)]
'''
# Emulate Bag.sortedByCount from Smalltalk
if n is None:
return sorted(self.items(), key=_itemgetter(1), reverse=True)
return _heapq.nlargest(n, self.items(), key=_itemgetter(1))
def elements(self):
'''Iterator over elements repeating each as many
times as its count.
>>> c = Counter('ABCABC')
>>> sorted(c.elements())
['A', 'A', 'B', 'B',
'C', 'C']
# Knuth's example for prime factors of 1836: 2**2 * 3**3 *
17**1
>>> prime_factors = Counter({2: 2, 3: 3, 17: 1})
>>> product = 1
>>> for factor in prime_factors.elements(): # loop
over factors
... product *= factor # and multiply them
>>> product
1836
Note, if an element's count has been set to zero or is a
negative
number, elements() will ignore it.
'''
# Emulate Bag.do from Smalltalk and Multiset.begin from C++.
return _chain.from_iterable(_starmap(_repeat, self.items()))
# Override dict methods where necessary
@classmethod
def fromkeys(cls, iterable, v=None):
# There is no equivalent method for counters because setting v=1
# means that no element can have a count greater than one.
raise NotImplementedError(
'Counter.fromkeys() is undefined. Use Counter(iterable)
instead.')
def update(*args, **kwds):
'''Like dict.update() but add counts instead of
replacing them.
Source can be an iterable, a dictionary, or another Counter
instance.
>>> c = Counter('which')
>>> c.update('witch') # add elements
from another iterable
>>> d = Counter('watch')
>>> c.update(d) # add elements from
another counter
>>> c['h'] # four
'h' in which, witch, and watch
4
'''
# The regular dict.update() operation makes no sense here because
the
# replace behavior results in the some of original untouched counts
# being mixed-in with all of the other counts for a mismash that
# doesn't have a straight-forward interpretation in most
counting
# contexts. Instead, we implement straight-addition. Both the
inputs
# and outputs are allowed to contain zero and negative counts.
if not args:
raise TypeError("descriptor 'update' of
'Counter' object "
"needs an argument")
self = args[0]
args = args[1:]
if len(args) > 1:
raise TypeError('expected at most 1 arguments, got
%d' % len(args))
iterable = args[0] if args else None
if iterable is not None:
if isinstance(iterable, Mapping):
if self:
self_get = self.get
for elem, count in iterable.items():
self[elem] = count + self_get(elem, 0)
else:
super(Counter, self).update(iterable) # fast path when
counter is empty
else:
_count_elements(self, iterable)
if kwds:
self.update(kwds)
def subtract(*args, **kwds):
'''Like dict.update() but subtracts counts instead
of replacing them.
Counts can be reduced below zero. Both the inputs and outputs are
allowed to contain zero and negative counts.
Source can be an iterable, a dictionary, or another Counter
instance.
>>> c = Counter('which')
>>> c.subtract('witch') # subtract
elements from another iterable
>>> c.subtract(Counter('watch')) # subtract
elements from another counter
>>> c['h'] # 2 in
which, minus 1 in witch, minus 1 in watch
0
>>> c['w'] # 1 in
which, minus 1 in witch, minus 1 in watch
-1
'''
if not args:
raise TypeError("descriptor 'subtract' of
'Counter' object "
"needs an argument")
self = args[0]
args = args[1:]
if len(args) > 1:
raise TypeError('expected at most 1 arguments, got
%d' % len(args))
iterable = args[0] if args else None
if iterable is not None:
self_get = self.get
if isinstance(iterable, Mapping):
for elem, count in iterable.items():
self[elem] = self_get(elem, 0) - count
else:
for elem in iterable:
self[elem] = self_get(elem, 0) - 1
if kwds:
self.subtract(kwds)
def copy(self):
'Return a shallow copy.'
return self.__class__(self)
def __reduce__(self):
return self.__class__, (dict(self),)
def __delitem__(self, elem):
'Like dict.__delitem__() but does not raise KeyError for
missing values.'
if elem in self:
super(Counter, self).__delitem__(elem)
def __repr__(self):
if not self:
return '%s()' % self.__class__.__name__
try:
items = ', '.join(map('%r: %r'.__mod__,
self.most_common()))
return '%s({%s})' % (self.__class__.__name__, items)
except TypeError:
# handle case where values are not orderable
return '{0}({1!r})'.format(self.__class__.__name__,
dict(self))
# Multiset-style mathematical operations discussed in:
# Knuth TAOCP Volume II section 4.6.3 exercise 19
# and at http://en.wikipedia.org/wiki/Multiset
#
# Outputs guaranteed to only include positive counts.
#
# To strip negative and zero counts, add-in an empty counter:
# c += Counter()
def __add__(self, other):
'''Add counts from two counters.
>>> Counter('abbb') + Counter('bcc')
Counter({'b': 4, 'c': 2, 'a': 1})
'''
if not isinstance(other, Counter):
return NotImplemented
result = Counter()
for elem, count in self.items():
newcount = count + other[elem]
if newcount > 0:
result[elem] = newcount
for elem, count in other.items():
if elem not in self and count > 0:
result[elem] = count
return result
def __sub__(self, other):
''' Subtract count, but keep only results with
positive counts.
>>> Counter('abbbc') - Counter('bccd')
Counter({'b': 2, 'a': 1})
'''
if not isinstance(other, Counter):
return NotImplemented
result = Counter()
for elem, count in self.items():
newcount = count - other[elem]
if newcount > 0:
result[elem] = newcount
for elem, count in other.items():
if elem not in self and count < 0:
result[elem] = 0 - count
return result
def __or__(self, other):
'''Union is the maximum of value in either of the
input counters.
>>> Counter('abbb') | Counter('bcc')
Counter({'b': 3, 'c': 2, 'a': 1})
'''
if not isinstance(other, Counter):
return NotImplemented
result = Counter()
for elem, count in self.items():
other_count = other[elem]
newcount = other_count if count < other_count else count
if newcount > 0:
result[elem] = newcount
for elem, count in other.items():
if elem not in self and count > 0:
result[elem] = count
return result
def __and__(self, other):
''' Intersection is the minimum of corresponding
counts.
>>> Counter('abbb') &
Counter('bcc')
Counter({'b': 1})
'''
if not isinstance(other, Counter):
return NotImplemented
result = Counter()
for elem, count in self.items():
other_count = other[elem]
newcount = count if count < other_count else other_count
if newcount > 0:
result[elem] = newcount
return result
def __pos__(self):
'Adds an empty counter, effectively stripping negative and
zero counts'
return self + Counter()
def __neg__(self):
'''Subtracts from an empty counter. Strips positive
and zero counts,
and flips the sign on negative counts.
'''
return Counter() - self
def _keep_positive(self):
'''Internal method to strip elements with a negative
or zero count'''
nonpositive = [elem for elem, count in self.items() if not count
> 0]
for elem in nonpositive:
del self[elem]
return self
def __iadd__(self, other):
'''Inplace add from another counter, keeping only
positive counts.
>>> c = Counter('abbb')
>>> c += Counter('bcc')
>>> c
Counter({'b': 4, 'c': 2, 'a': 1})
'''
for elem, count in other.items():
self[elem] += count
return self._keep_positive()
def __isub__(self, other):
'''Inplace subtract counter, but keep only results
with positive counts.
>>> c = Counter('abbbc')
>>> c -= Counter('bccd')
>>> c
Counter({'b': 2, 'a': 1})
'''
for elem, count in other.items():
self[elem] -= count
return self._keep_positive()
def __ior__(self, other):
'''Inplace union is the maximum of value from either
counter.
>>> c = Counter('abbb')
>>> c |= Counter('bcc')
>>> c
Counter({'b': 3, 'c': 2, 'a': 1})
'''
for elem, other_count in other.items():
count = self[elem]
if other_count > count:
self[elem] = other_count
return self._keep_positive()
def __iand__(self, other):
'''Inplace intersection is the minimum of
corresponding counts.
>>> c = Counter('abbb')
>>> c &= Counter('bcc')
>>> c
Counter({'b': 1})
'''
for elem, count in self.items():
other_count = other[elem]
if other_count < count:
self[elem] = other_count
return self._keep_positive()
def check_output(*popenargs, **kwargs):
"""
For Python 2.6 compatibility: see
http://stackoverflow.com/questions/4814970/
"""
if 'stdout' in kwargs:
raise ValueError('stdout argument not allowed, it will be
overridden.')
process = subprocess.Popen(stdout=subprocess.PIPE, *popenargs,
**kwargs)
output, unused_err = process.communicate()
retcode = process.poll()
if retcode:
cmd = kwargs.get("args")
if cmd is None:
cmd = popenargs[0]
raise subprocess.CalledProcessError(retcode, cmd)
return output
def count(start=0, step=1):
"""
``itertools.count`` in Py 2.6 doesn't accept a step
parameter. This is an enhanced version of ``itertools.count``
for Py2.6 equivalent to ``itertools.count`` in Python 2.7+.
"""
while True:
yield start
start += step
########################################################################
### ChainMap (helper for configparser and string.Template)
### From the Py3.4 source code. See also:
### https://github.com/kkxue/Py2ChainMap/blob/master/py2chainmap.py
########################################################################
class ChainMap(MutableMapping):
''' A ChainMap groups multiple dicts (or other mappings)
together
to create a single, updateable view.
The underlying mappings are stored in a list. That list is public and
can
accessed or updated using the *maps* attribute. There is no other
state.
Lookups search the underlying mappings successively until a key is
found.
In contrast, writes, updates, and deletions only operate on the first
mapping.
'''
def __init__(self, *maps):
'''Initialize a ChainMap by setting *maps* to the
given mappings.
If no mappings are provided, a single empty dictionary is used.
'''
self.maps = list(maps) or [{}] # always at least one map
def __missing__(self, key):
raise KeyError(key)
def __getitem__(self, key):
for mapping in self.maps:
try:
return mapping[key] # can't use 'key
in mapping' with defaultdict
except KeyError:
pass
return self.__missing__(key) # support subclasses that
define __missing__
def get(self, key, default=None):
return self[key] if key in self else default
def __len__(self):
return len(set().union(*self.maps)) # reuses stored hash values
if possible
def __iter__(self):
return iter(set().union(*self.maps))
def __contains__(self, key):
return any(key in m for m in self.maps)
def __bool__(self):
return any(self.maps)
# Py2 compatibility:
__nonzero__ = __bool__
@recursive_repr()
def __repr__(self):
return '{0.__class__.__name__}({1})'.format(
self, ', '.join(map(repr, self.maps)))
@classmethod
def fromkeys(cls, iterable, *args):
'Create a ChainMap with a single dict created from the
iterable.'
return cls(dict.fromkeys(iterable, *args))
def copy(self):
'New ChainMap or subclass with a new copy of maps[0] and refs
to maps[1:]'
return self.__class__(self.maps[0].copy(), *self.maps[1:])
__copy__ = copy
def new_child(self, m=None): # like Django's
Context.push()
'''
New ChainMap with a new map followed by all previous maps. If no
map is provided, an empty dict is used.
'''
if m is None:
m = {}
return self.__class__(m, *self.maps)
@property
def parents(self): # like Django's
Context.pop()
'New ChainMap from maps[1:].'
return self.__class__(*self.maps[1:])
def __setitem__(self, key, value):
self.maps[0][key] = value
def __delitem__(self, key):
try:
del self.maps[0][key]
except KeyError:
raise KeyError('Key not found in the first mapping:
{0!r}'.format(key))
def popitem(self):
'Remove and return an item pair from maps[0]. Raise KeyError
is maps[0] is empty.'
try:
return self.maps[0].popitem()
except KeyError:
raise KeyError('No keys found in the first mapping.')
def pop(self, key, *args):
'Remove *key* from maps[0] and return its value. Raise
KeyError if *key* not in maps[0].'
try:
return self.maps[0].pop(key, *args)
except KeyError:
raise KeyError('Key not found in the first mapping:
{0!r}'.format(key))
def clear(self):
'Clear maps[0], leaving maps[1:] intact.'
self.maps[0].clear()
# Re-use the same sentinel as in the Python stdlib socket module:
from socket import _GLOBAL_DEFAULT_TIMEOUT
# Was: _GLOBAL_DEFAULT_TIMEOUT = object()
def create_connection(address, timeout=_GLOBAL_DEFAULT_TIMEOUT,
source_address=None):
"""Backport of 3-argument create_connection() for Py2.6.
Connect to *address* and return the socket object.
Convenience function. Connect to *address* (a 2-tuple ``(host,
port)``) and return the socket object. Passing the optional
*timeout* parameter will set the timeout on the socket instance
before attempting to connect. If no *timeout* is supplied, the
global default timeout setting returned by :func:`getdefaulttimeout`
is used. If *source_address* is set it must be a tuple of (host, port)
for the socket to bind as a source address before making the
connection.
An host of '' or port 0 tells the OS to use the default.
"""
host, port = address
err = None
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
af, socktype, proto, canonname, sa = res
sock = None
try:
sock = socket(af, socktype, proto)
if timeout is not _GLOBAL_DEFAULT_TIMEOUT:
sock.settimeout(timeout)
if source_address:
sock.bind(source_address)
sock.connect(sa)
return sock
except error as _:
err = _
if sock is not None:
sock.close()
if err is not None:
raise err
else:
raise error("getaddrinfo returns an empty list")
# Backport from Py2.7 for Py2.6:
def cmp_to_key(mycmp):
"""Convert a cmp= function into a key=
function"""
class K(object):
__slots__ = ['obj']
def __init__(self, obj, *args):
self.obj = obj
def __lt__(self, other):
return mycmp(self.obj, other.obj) < 0
def __gt__(self, other):
return mycmp(self.obj, other.obj) > 0
def __eq__(self, other):
return mycmp(self.obj, other.obj) == 0
def __le__(self, other):
return mycmp(self.obj, other.obj) <= 0
def __ge__(self, other):
return mycmp(self.obj, other.obj) >= 0
def __ne__(self, other):
return mycmp(self.obj, other.obj) != 0
def __hash__(self):
raise TypeError('hash not implemented')
return K
# Back up our definitions above in case they're useful
_OrderedDict = OrderedDict
_Counter = Counter
_check_output = check_output
_count = count
_ceil = ceil
__count_elements = _count_elements
_recursive_repr = recursive_repr
_ChainMap = ChainMap
_create_connection = create_connection
_cmp_to_key = cmp_to_key
# Overwrite the definitions above with the usual ones
# from the standard library:
if sys.version_info >= (2, 7):
from collections import OrderedDict, Counter
from itertools import count
from functools import cmp_to_key
try:
from subprocess import check_output
except ImportError:
# Not available. This happens with Google App Engine: see issue
#231
pass
from socket import create_connection
if sys.version_info >= (3, 0):
from math import ceil
from collections import _count_elements
if sys.version_info >= (3, 3):
from reprlib import recursive_repr
from collections import ChainMap