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My server has Python2.5 I wanna be jump to newest Python (2.7.x in my case). I compiled python from source, I downloaded newest virtualenv (1.5.1).
Now basically what im trying to do:
./packages/virtualenv/virtualenv.py --python=packages/Python-2.7/python env/
Python 2.7 (r27:82500, Nov 21 2010, 23:19:15) [GCC 4.3.2] on linux2 (cut help mesage) >>>
However runing virutalenv results in:
AssertionError: Filename /packages/Python-2.7/Lib/os.py does not start with any of these prefixes: [‘/usr/local’]
Whatever it means and whatever I am or I am not doing wrong.
While building env + python I based at question: How do I work around this problem creating a virtualenv environment with a custom-build Python?
After reading and messing with this.
I found that this error might be related with lack of
--prefix while runing
./configure for python. So I’ve run
./configure --prefix=/Path/To/Where/I/Want/Python/After/Compilation/ (in my case
$HOME/packages/Python-2.7), then I’ve typed
make install (without using
sudo – so python was safely put into where I told it to be as current user not root). After that virtualenv initiation did not crash with
AssertionError and everything worked like a charm.
Hope that this question answered by author will eventually help someone. 🙂
I don’t have enough rep to add this as a comment and this question is 3 years old, but this might be useful to someone. In Windows, you have to path out to python.exe, but it seems that in Linux/OS X you just path to the folder. Example:
virtualenv -p <PATH TO PYTHON.EXE> venv
Creates a virtual environment in subfolder “venv” in current directory.
I don’t have enough rep to add comment. Mike’s answer save my day. I’m using windows.
I was getting the error :
AssertionError: Filename C:\Python35\Lib\os.py does not start with any of these prefixes: ['c:\\python35', 'c:\\python35']
I had to run this-
virtualenv -p C:\Python35\python.exe venv
also need to run this from a cmd opened as Administrator. Otherwise getting the error
PermissionError: [WinError 5] Access is denied
Someone with enough reps to comment please add this to Mike’s answer as a comment. I’ll then clear mine.