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Python read-only property
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Generally, Python programs should be written with the assumption that all users are consenting adults, and thus are responsible for using things correctly themselves. However, in the rare instance where it just does not make sense for ...
“Could not run curl-config: [Errno 2] No such file or directory” when installing pycurl
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That fixed my issue on Ubuntu 12.04 (x64) and Python3.4 installed
– Ilia Shakitko
Dec 17 '14 at 11:13
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Why is “if not someobj:” better than “if someobj == None:” in Python?
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In the first test, Python try to convert the object to a bool value if it is not already one. Roughly, we are asking the object : are you meaningful or not ? This is done using the following algorithm :
If the object has a __nonzero__ special...
Iterating each character in a string using Python
...tring":
#do something with c
You can iterate pretty much anything in python using the for loop construct,
for example, open("file.txt") returns a file object (and opens the file), iterating over it iterates over lines in that file
with open(filename) as f:
for line in f:
# do so...
Python multiprocessing PicklingError: Can't pickle
... example, and my code is too complicated to post. If I run the program in IPython shell instead of the regular Python, things work out well.
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How to compare type of an object in Python?
...ce(obj, (MyClass, type(None))) works. types.NoneType has been removed from Python 3 so it is not as portable as type(None) to get a reference to NoneType.
– Santeri Paavolainen
Feb 17 '16 at 13:17
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Is there a difference between using a dict literal and a dict constructor?
...d BUILD_MAP and STORE_MAP opcodes rather than generic CALL_FUNCTION:
> python2.7 -m timeit "d = dict(a=1, b=2, c=3, d=4, e=5)"
1000000 loops, best of 3: 0.958 usec per loop
> python2.7 -m timeit "d = {'a':1, 'b':2, 'c':3, 'd':4, 'e':5}"
1000000 loops, best of 3: 0.479 usec per loop
> pyt...
How to add a custom loglevel to Python's logging facility
...ally log(5, msg) isn't what I want. How can I add a custom loglevel to a Python logger?
16 Answers
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Python - abs vs fabs
I noticed that in python there are two similar looking methods for finding the absolute value of a number:
4 Answers
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How to use timeit module
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If you want to use timeit in an interactive Python session, there are two convenient options:
Use the IPython shell. It features the convenient %timeit special function:
In [1]: def f(x):
...: return x*x
...:
In [2]: %timeit for x in range(100): f(x)
10...