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Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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jQuery using append with effects
...s wrong though and you're right, you can chain them. I've edited my answer now.
– Mark Bell
Oct 5 '09 at 14:15
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How do I initialize the base (super) class?
...t(foo)
Because python knows about old- and new-style classes, there are different ways to invoke a base method, which is why you've found multiple ways of doing so.
For completeness sake, old-style classes call base methods explicitly using the base class, i.e.
def doit(self, foo):
return X.do...
Set attributes from dictionary in python
...
If you pass initial data as def __init__(self,**initial_data) you get the added benefit of having an init method that can also do keyword arguments too (e.g. "e = Employee(name='Oscar')" or just take in a dictionary (e.g. "e ...
Where does PostgreSQL store the database?
...ific folder is painful as someone else might have installed it for you and now you do not know the configuration, so following sql helps to save the time. :) Thanks Mike.
– Vishal
Jun 14 '13 at 8:54
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Python multiprocessing pool.map for multiple arguments
...ort product
def merge_names(a, b):
return '{} & {}'.format(a, b)
if __name__ == '__main__':
names = ['Brown', 'Wilson', 'Bartlett', 'Rivera', 'Molloy', 'Opie']
with multiprocessing.Pool(processes=3) as pool:
results = pool.starmap(merge_names, product(names, repeat=2))
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python NameError: global name '__file__' is not defined
... shell when you C-c C-p? python-shell. Is there a way to use this shell as if it were a terminal running the file? There are 3 options for running the shell : CMD DEDICATED SHOW Would one of them do this?
– sinekonata
Jul 2 at 0:43
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In MySQL, how to copy the content of one table to another table within the same database?
...at w3school page is for a different SQL, not intended for MySQL. w3schools now has error reporting, if you find issues report it on their site to assist with accurate knowledge.
– Nightwolf
Sep 27 '17 at 10:50
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In pure functional languages, is there an algorithm to get the inverse function?
...n this result, as well as the number of times it can have called f. Define now a family of functions
g j (B1 : B0 : ... (n+j times) ... B0 : ls)
= B0 : ... (n+j times) ... B0 : B1 : ls
g j (B0 : ... (n+j times) ... B0 : B1 : ls)
= B1 : B0 : ... (n+j times) ... B0 : ls
g j l = l
Clearly, for...
How do I get the opposite (negation) of a Boolean in Python?
...> value = False
>>> not value
True
So instead of your code:
if bool == True:
return False
else:
return True
You could use:
return not bool
The logical negation as function
There are also two functions in the operator module operator.not_ and it's alias operator.__not__ i...