Change default Python interpreter on Windows XP
I have two python versions: Python 2.5 and Python 2.7. When I'm setting up django, I want to use Python 2.7, but django is using Python 2.5 somehow.
How can I make sure that django use Python 2.7? I'm using Windows XP
Change your PATH system environment variable to point to the version of Python you want to use.
Changing your PATH will help, if you always call python directly, rather than relying on file association.
For example: "python foo.py" will run the 'foo' script with whichever python is first on your PATH.
However, if you just run "foo.py", the handler associated in the registry, for this file extension, will be the first one called.
In your case, it sounds like that would be python 2.5. Have a look by opening regedit, and checking the values of:
The (default) value listed will probably be something like "C:\Python25\python.exe" "%1" %*
A quick (and dirty?) fix for you would be to change these values to the python version you actually want.
A better fix would be to do something like what's outlined in this feature request:
Since then, as long as you had admin rights, you could switch as you needed by pointing assoc at the version you want quickly.
Make two simple .cmd files:
@echo off set PYTHONHOME=c:\python25 set PATH=%PATH%;c:\python25
@echo off set PYTHONHOME=c:\python27 set PATH=%PATH%;c:\python27
Now you can switch between Python 2.5 and 2.7. :)
Python installer does no change to PATH environment variable under windows. When typing something like python setup.py windows first looks for python in PATH, then in current user registry hive
and then in local machine registry hive
Now that Python 3.3 is released it is easiest to use the py.exe utility described here: http://www.python.org/dev/peps/pep-0397/
It allows you to specify a Python version in your script file using a UNIX style directive. There are also command line and environment variable options for controlling which version of Python is run.
The easiest way to get this utility is to install Python 3.3 or later.
If you want to switch between Python 2.x and Python 3.x then easiest way is to use Python Launcher which is included since 3.3 version. This is basically py.exe in Windows folder. To start Python 3.x command prompt, just type
To execute script with Python 3.x, use
py -3 script.py
If you don't specify -3 then 2.x version is used by default. You can also make this explicit by using -2.7 switch.
py -2.7 script.py
Finally, you can now embed the version number to use in .script file itself. This works because after Python 3.3+ is installed, it associated py.exe with .py files.
#! python3 import sys sys.stdout.write("hello from Python %s\n" % (sys.version,))
Change the registry key at