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How to enumerate an object's properties in Python?
...oes not return dynamic members (i.e., object attributes and methods dynamically defined by that object's __getattr__() method or similar magic). In all likelihood, your desired file.ImplementationName property is defined dynamically and hence not available to vars() or dir().
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What is the purpose of the -m switch?
Could you explain to me what the difference is between calling
3 Answers
3
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Difference between a theta join, equijoin and natural join
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A theta join allows for arbitrary comparison relationships (such as ≥).
An equijoin is a theta join using the equality operator.
A natural join is an equijoin on attributes that have the same name in each relationship.
Additionally,...
Difference between String replace() and replaceAll()
What's the difference between java.lang.String 's replace() and replaceAll() methods,
other than later uses regex? For simple substitutions like, replace . with / ,
is there any difference?
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Why does Python use 'magic methods'?
...lable, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
7 Answers
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How do I get the path of the current executed file in Python?
...ike a newbie question, but it is not. Some common approaches don't work in all cases:
13 Answers
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Dictionary vs Object - which is more efficient and why?
...ots__ = ('i', 'l')
def __init__(self, i):
self.i = i
self.l = []
all = {}
for i in range(1000000):
all[i] = Obj(i)
test_obj.py:
class Obj(object):
def __init__(self, i):
self.i = i
self.l = []
all = {}
for i in range(1000000):
all[i] = Obj(i)
test_dict.py:
all = {}
for i in...
How to get the parents of a Python class?
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If you want all the ancestors rather than just the immediate ones, use inspect.getmro:
import inspect
print inspect.getmro(cls)
Usefully, this gives you all ancestor classes in the "method resolution order" -- i.e. the order in which ...
Build a Basic Python Iterator
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Iterator objects in python conform to the iterator protocol, which basically means they provide two methods: __iter__() and __next__().
The __iter__ returns the iterator object and is implicitly called
at the start of loops.
The __next__() method returns the next value and is implicitly cal...
How to combine two or more querysets in a Django view?
...sets into a list is the simplest approach. If the database will be hit for all querysets anyway (e.g. because the result needs to be sorted), this won't add further cost.
from itertools import chain
result_list = list(chain(page_list, article_list, post_list))
Using itertools.chain is faster than...