Python is an interpreted, general, high-level programming language. Programming questions are off topic. Questions about the use of Python and should be asked at [Stack Overflow](http://www.stackoverflow.com).

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41
votes
7answers
24k views

emacs: how to indent/unindent region of python code by 4 spaces?

I have a region of python code selected in emacs. What are the most efficient ways to indent and unindent every line in it by 4 spaces? Ideally I'd like something that's not context sensitive (eg. ...
25
votes
5answers
75k views

How can I change the default Python version on Snow Leopard?

I recently upgraded my Mac OS X 10.5 Leopard install to 10.6 Snow Leopard, and with that came an upgraded version of Python, 2.6.1 (instead if 2.5.1). Now when I type python in the Terminal i still ...
23
votes
3answers
5k views

Find outdated/updatable pip packages

pip freeze shows me the packages installed, but how do I check against pypi which ones are outdated?
21
votes
7answers
84k views

Updating Python on Ubuntu system

I want to update the Python build on my Linux box, but the only way I know how to do it is uninstalling the current version and installing the new one. My system is already up to date (I updated ...
21
votes
4answers
43k views

How To Add Python to the Windows Path

How do I add python to the windows PATH permanently?
20
votes
3answers
73k views

How to globally modify the default PYTHONPATH (sys.path)?

On a Ubuntu (10.10) system, I have a Python package that installs itself into /usr/local/lib/python2.6/site-packages/. This isn't contained in the default path (sys.path). How do I add this directory ...
18
votes
6answers
12k views

How to simulate slow internet connection

I currently deploy with GAE (google app engine) and I try to implement some AJAX validation. So I got a couple text-fields and "spinners" (ajax loaders) which should be displayed when an AJAX request ...
17
votes
10answers
18k views

How to install matplotlib on OS X?

I want to install matplotlib on OS X. If possible, using homebrew. I installed Python 2.7.1 using brew install python, I modified my path to use it I installed pip using brew install pip I installed ...
17
votes
3answers
20k views

easy_install will not connect through proxy

I'm running Ubuntu Server 10.04 64-bit under VirtualBox, and it seems that everything except easy_install and pip can connect to the Internet. I have set and exported the http_proxy environment ...
16
votes
2answers
7k views

Run Python scripts without explicitly invoking `python`

I'm using Debian Linux. I was wondering if there was a way to configure to run all Python scripts in the terminal by typing script.py (instead of python script.py).
16
votes
8answers
78k views

How to install pip and easy_install on CentOS

I tried to install pip and easy_install on my CentOS but could not find them. How can I install them? Also, I have two versions of Python, 2.4 and 2.7. How will pip make sure to link newly installed ...
16
votes
6answers
31k views

installing wxpython via pip or easy_install

I am running into some problems installing wxpython using pip. Here is my current output: [myuserid]% sudo pip install wxpython Downloading/unpacking wxpython Downloading ...
15
votes
2answers
15k views

How to use Latest Python 2.7.x “The Right Way” on Ubuntu 12.04 LTS?

My project needs to stay current on Python releases, but 12.04LTS is currently stuck on 2.7.3, even though 2.7.5 is out now. Is there a way I can stay more current without manually compiling? We're ...
14
votes
6answers
3k views

What is the best method to remove duplicate image files from your computer?

I have a lot of duplicate image files on my Windows computer, in different subfolders and with different file names. What Python script or freeware program would you recommend for removing the ...
13
votes
2answers
4k views

How can I use the Homebrew Python with Homebrew MacVim on Mountain Lion?

I originally asked and answered this question: How can I use the Homebrew Python version with Homebrew MacVim? These instructions worked on Snow Leopard using Xcode 4.0.1 and associated developer ...
13
votes
9answers
11k views

Vim: execute the script I'm working on in a split screen

I'm working on a small python script, which needs frequent execution in order to debug and further develop. Can I split the vim screen and execute my script on one part with a keystroke?
13
votes
1answer
2k views

Why is Python for Windows not installed in %PROGRAMFILES% (“C:\Program Files”)?

Python was originally installed in C:\Program Files\Python, but that changed around 1.5. What was the reasoning behind that decision? Is it a bad idea to change the directory back, and if so, why?
13
votes
1answer
4k views

How can I use the Homebrew Python version with Homebrew MacVim on Snow Leopard?

Note: For Mountain Lion, see: How can I use the Homebrew Python with Homebrew MacVim on Mountain Lion? I've installed Python 2.7 with Homebrew on Mac OS X Snow Leopard. When I install MacVim ...
13
votes
4answers
47k views

How do I write code of more than 1 line in the Python interpreter?

I have a problem coding Python in terminal. I'm just learning basics so I have no need to create .py files. In terminal I can run one line of code in the Python interpreter, but how do I write more ...
13
votes
0answers
813 views

Jenkins realtime console output for parallel threaded fabric command

We have a Python fabric command that runs in parallel across several hosts, something like this: $ fab --hosts=prod1.server,prod2.server,prod3.server --parallel copy_cache This will copy cache to ...
12
votes
1answer
22k views

How to find installation path for packages installed through apt-get in Ubuntu?

I have been installing python modules using apt-get which works great using the console or launching files from the command line. However I am using Eclipse for easier organisation of files. Eclipse ...
12
votes
3answers
12k views

How can I make a table of contents for a markdown document with Python/AWK/SED?

I have the following markdown document: Heading-a ========== ---text--- Heading-b ------------ --- text --- Heading-c ---------- --- text--- Heading-d ======= --- text---- Heading-e --- ... ...
11
votes
2answers
17k views

Python / Selenium / PhantomJS: “Unable to start phantomjs with ghostdriver.”

I'm trying to get Selenium to use phantomjs on a Windows machine. My code compiles without any error: from selenium import webdriver from selenium.webdriver.common.desired_capabilities import ...
11
votes
3answers
6k views

Python 2.6.1, pycrypto 2.3 pypi package: “Broken Pipe” during build

I am attempting to install Fabric, which requires pycrypto. During the build for pycrypto I always receive a "Broken Pipe" error. I don't know where to start to fix the problem. I'm running Mac OS X ...
11
votes
1answer
6k views

enabling colors in the python interactive shell on OS/X

I have just modified my .bash_profile so as to have colors in iTerm and Terminal. Now, I want to enable syntax highlighting for the Python interactive shell, IDLE-style. How to do that?
11
votes
1answer
4k views

How to set up a own Chrome sync server?

I'm trying to set up a sync server for Chromium/Chrome, but i'm totally failed. I also couldn't find a How-To (like this here for Firefox) for that. I only found this question from '10 on superuser ...
10
votes
6answers
6k views

Force output buffer flush in running program

I have a long-running python script that periodically outputs data to standard output that I've invoked with something like: python script.py > output.txt This script has been running for a ...
10
votes
2answers
3k views

%paste magic function on ipython3

I'm using ipython3, installed on Ubuntu with apt-get. I can't use the paste magic function, it complains about missing Tkinter. But I do have Tkinter and the same thing works fine on ipython (2). ...
9
votes
13answers
25k views

Scripting: what is the easiest to extact a value in a tag of a XML file?

I want to read a pom.xml ('Project Object Model' of Maven) and extract the version information. Here is an example: <?xml version="1.0" encoding="UTF-8"?><project ...
9
votes
3answers
857 views

How can I run my python program directly from the shell?

I wrote a script. When it starts, it won't stop, and it keeps getting data from the Internet. I can call it this way: cd /User/Desktop/project/internetScanner/ python3 main.py start But I would ...
9
votes
5answers
10k views

Adding programming code into LaTex / LyX

Maybe I'm just being thick, but I can't find any sensible way to simply paste in my (python) code into latex without losing all the indent information (kinda important for python). Anyone got any ...
9
votes
5answers
22k views

How can I open Python files in IDLE from Windows?

I'm new to Python. I use Python 2.7 and I am running Windows Vista (64-bit). How do I make it when I click on .py scripts... that it opens up in IDLE so I can edit it a snap? Ya know... without having ...
9
votes
4answers
20k views

Error Installing python on Windows 7 x64

I am on Windows 7 x64, trying to install Python 2.7.5 or 3.3.2. But I'm continuously getting an error showing : "There is a Problem with this windows installer package. A DLL required for this install ...
8
votes
2answers
8k views

How to increase Python's CPU usage

I use Python to execute some algorithms and no matter which Python I use, and I have tried many versions, the CPU usage goes to 25% max. Why doesn't Python take advantage of the rest of my CPU ...
8
votes
6answers
8k views

Installing pygame on Snow Leopard's system Python 2.6

Snow leopard has python 2.6 included now, and I want to install pygame on it, but it says its for Python from python.org, not system python. I tried using setup.py from source, but it didn't work. Is ...
8
votes
2answers
107 views

Is it possible to modify bash to run one command through another (say a python script)?

I was wondering if it is possible to modify bash such that when I type command --arg1 what actually happens is ~/prerun.py command --arg1 (prerun.py would handle starting command --arg1 itself) ...
8
votes
4answers
20k views

How do I make a script run upon startup of the Ubuntu machine?

I want to run /home/myuser/go.py How do I make that run in the background, everytime my linux machine boots up?
8
votes
2answers
23k views

python3-pip installed but pip3 command not found?

I am testing a Python3 program in several computers. To do that, I need to install a library of Python with pip3. So first, I was installing python3-pip in each computer (everyone is running a ...
7
votes
2answers
27k views

Why is pip not listed in easy_install on CentOS 6? Where to get it?

I am trying to install pip for python on CentOS 6. I thought of installing it through easy_install but it is not there. I tried to find easy_install with find command, but no luck. I tried to ...
7
votes
4answers
3k views

Run pip for python3 on Fedora

I can't run pip for python3 (3.4) on Fedora 22. Pip for python2.7 is installed on system by default and works fine. I install package python3-pip but can't run it. pip3, pip-3.4, python3-pip, python3 ...
7
votes
3answers
1k views

`which python` points to the python I want, but `python` runs the wrong version

I want to use python24 provided by ports, so I've installed it, and python_select -s shows that the version I want is indeed selected. Running which python gives /opt/local/bin/python, and running ...
7
votes
6answers
3k views

How do I change the file association to a program with the same name in Windows 7?

Windows 7's file association controls have been "simplified" and now I appear to be unable to change the default association of a file (in my case a Python script) to a different executable. If I ...
7
votes
2answers
1k views

OS-X terminal behaves oddly after running Python interactively

After running a python repl (2.7.10) in the os-x terminal and exiting, the terminal no longer echos typed input and some other strange things happen. If I run python again and exit(), then the ...
7
votes
2answers
3k views

cron can't read PYTHONPATH environment variables?

I have added to the PYTHONPATH on my server's .bash_profile file. However it appears that cron isn't reading from it because I am getting import errors. If I run the exact command cron calls on the ...
7
votes
4answers
1k views

Can't type the “b” letter in Python shell in OS X

I have a problem with my "b" letter in Python shell in OS X. I can't type "b", but "B" worked fine. How can I solve this issue?
7
votes
5answers
2k views

How can I prevent the python.el that ships with Emacs 23 from EVER loading?

I use python-mode.el instead of python.el for python work, and all of my customizations depend on it. However, periodically for some reason the python.el that ships with Emacs23 will magically get ...
7
votes
1answer
947 views

Get Python to raise MemoryError instead of eating all my disk space

If I run a Python program with a memory leak, I would normally expect the program to eventually die with MemoryError. But instead, what happens is that all the virtual memory is used until my disk ...
7
votes
2answers
14k views

“Cannot allocate memory” while no process seems to be using up memory

I am not competent on server issues, any help is much appreciated. When try to start a python/django shell on a linux box, I am getting OSError: [Errno 12] Cannot allocate memory. free -m seems to ...
7
votes
4answers
9k views

Making `#!/usr/bin/env python` work on Windows

I use Bash on Windows, provided by MSYS. I tried to run a Python file with a shebang of #!/usr/bin/env python, but I get this error message: /usr/bin/env: python: No such file or directory What ...
7
votes
3answers
10k views

How to update Mac's system Python

I'm on Mavericks at the moment, and i want to update the Python system's version (2.7.5) to the latest (2.7.7) from http://www.python.org, because i want to install pygame. What i have to do? I would ...