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Is module __file__ attribute absolute or relative?
I'm having trouble understanding __file__ . From what I understand, __file__ returns the absolute path from which the module was loaded.
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How do I get the number of elements in a list?
...objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is cached. So checking the number of objects in a list is very fast.
But if you're checking if list size is zero or not, don't use len - instead, put the list in a boolean co...
How to call Base Class's __init__ method from the child class? [duplicate]
...
You could use super(ChildClass, self).__init__()
class BaseClass(object):
def __init__(self, *args, **kwargs):
pass
class ChildClass(BaseClass):
def __init__(self, *args, **kwargs):
super(ChildClass, self).__init__(*args, **kwargs)
You...
How to override the [] operator in Python?
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You need to use the __getitem__ method.
class MyClass:
def __getitem__(self, key):
return key * 2
myobj = MyClass()
myobj[3] #Output: 6
And if you're going to be setting values you'll need to implement the __setitem__ method too,...
How to extract the year from a Python datetime object?
...ew times and you'll be prompted with the members of the "now" object:
now.__add__ now.__gt__ now.__radd__ now.__sub__ now.fromordinal now.microsecond now.second now.toordinal now.weekday
now.__class__ now.__hash__ ...
C++ mark as deprecated
...his all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
7 Answers
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Python != operation vs “is not”
...ght hand side and the left hand side are equal objects (according to their __eq__ or __cmp__ methods.)
is is an identity test. It checks whether the right hand side and the left hand side are the very same object. No methodcalls are done, objects can't influence the is operation.
You use is (and i...
Print all properties of a Python Class [duplicate]
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vars only works if you are using __dict__ to store the attributes (which is the default behaviour for Python objects). Refer to @BasicWolf's answer if you are using __slots__
– Cyctemic
Feb 20 '14 at 10:23
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How to implement an ordered, default dict? [duplicate]
...eredDict):
# Source: http://stackoverflow.com/a/6190500/562769
def __init__(self, default_factory=None, *a, **kw):
if (default_factory is not None and
not isinstance(default_factory, Callable)):
raise TypeError('first argument must be callable')
Ordered...
Find current directory and file's directory [duplicate]
...ory a Python file is contained in, write this in that file:
import os
dir_path = os.path.dirname(os.path.realpath(__file__))
(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relativ...