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Double Iteration in List Comprehension
In Python you can have multiple iterators in a list comprehension, like
10 Answers
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A python class that acts like dict
... self.__dict__ is not the same as the actual dictionary content. Every python object, regardless of its type, has a _dict__ which contains all the object attributes (methods, fields, etc). You do not want to mess around with this unless you want to write code that is modifying itself...
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How do I deal with certificates using cURL while trying to access an HTTPS url?
...r is related to a missing package: ca-certificates. Install it.
In Ubuntu Linux (and similar distro):
# apt-get install ca-certificates
In CygWin via Apt-Cyg
# apt-cyg install ca-certificates
In Arch Linux (Raspberry Pi)
# pacman -S ca-certificates
The documentation tells:
This packa...
How to get the parents of a Python class?
How can I get the parent class(es) of a Python class?
6 Answers
6
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Define a lambda expression that raises an Exception
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There is more than one way to skin a Python:
y = lambda: (_ for _ in ()).throw(Exception('foobar'))
Lambdas accept statements. Since raise ex is a statement, you could write a general purpose raiser:
def raise_(ex):
raise ex
y = lambda: raise_(Excepti...
Concurrent.futures vs Multiprocessing in Python 3
Python 3.2 introduced Concurrent Futures , which appear to be some advanced combination of the older threading and multiprocessing modules.
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Java and SQLite [closed]
...atform JDBC driver which uses embedded native SQLite libraries on Windows, Linux, OS X, and falls back to pure Java implementation on other OSes: https://github.com/xerial/sqlite-jdbc (formerly zentus)
Another Java - SWIG wrapper. It only works on Win32. http://rodolfo_3.tripod.com/index.html
sqlite...
Where is virtualenvwrapper.sh after pip install?
...d to .profile, pointing towards virtualenvwrapper.sh. I've checked all the python and site-packages directories, and I can't find any virtualenvwrapper.sh. Is this something I need to download separately? Is pip not installing correctly?
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u'\ufeff' in Python string
...endian UTF-16 encoding. If you decode the web page using the right codec, Python will remove it for you. Examples:
#!python2
#coding: utf8
u = u'ABC'
e8 = u.encode('utf-8') # encode without BOM
e8s = u.encode('utf-8-sig') # encode with BOM
e16 = u.encode('utf-16') # encode with BOM
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How to view files in binary from bash?
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...and it's preinstalled on Mac OS X and on Linux.
– Sridhar Sarnobat
Sep 5 '17 at 22:36
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