Where is python2 if python points to python3?

Question

I installed python3 first on my PC. Now python launches python3 in a command prompt. When I tried to run a node app with a python2 dependency, I got an error about syntax (it was using the old print syntax):

gyp ERR! stack Error: Command failed: 
C:\Users\User\AppData\Local\Programs\Python\Python38-32\python.EXE -c import 
sys; print "%s.%s.%s" % sys.version_info[:3];

But I don't know how to make python point to python2.

Windows uses a PATH variable, although I don't use Windows all that often anymore, so I can't remember exactly where to find it -- but you will want to ensure that the python2 path is in the PATH before the python3.exe... — kojiro, Sep 30 '20 at 17:52
To make python point to python2, go to `python2` directory and copy `python2.exe` as `python` in the same directory, then add this folder to `PATH` — Shivam Jha, Sep 30 '20 at 17:54
This is an OS question. You need to search for your Python2 installation -- likely under the Programs\Python folder -- and either alter your PATH variable to point there, or create an alias (shortcut) for python2. See your OS documentation for how to handle those variables. — Prune, Sep 30 '20 at 17:55
@kojiro - this is the right answer. It was the ORDER of the path variables — JacobIRR, Sep 30 '20 at 17:58

score 0 · Answer 1 · answered Sep 30 '20 at 17:53

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You need to change your Windows environment variable to point to the python you want to use.

That's most likely where node is going to find the path for a usable python.exe.

answered Sep 30 '20 at 17:53

Clinton Bradfield

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score 0 · Answer 2 · answered Sep 30 '20 at 17:54

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You just need to change the env variable

similar question reference

answered Sep 30 '20 at 17:54

Coleone

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score 0 · Answer 3 · answered Sep 30 '20 at 17:57

Alternate solution: Never run python. The Windows solution, assuming Python 3 was installed with administrative privileges (so it could install the Python launcher), is to run:

 py -2

to run Python 2, and

 py -3

to run Python 3. The launcher was created specifically because the name is always python.exe on Windows, so only one version could ever be found in the PATH; the launcher grants access to all installed copies without manipulating PATH. Doesn't even require extra typing (py -2 being shorter than python).

score 0 · Answer 4 · answered Sep 30 '20 at 17:59

The Python installer installs PyLauncher unless you deselected it. Don't add python to the PATH. py.exe (the launcher) is installed in the path already (C:\Windows by default).

py -2   # launches latest python 2 installed.
py -3   # launches latest python 3 installed.
py -3.6 # launches Python 3.6.

The PY_PYTHON environment variable can be set, e.g. set PY_PYTHON=3.6 to select a default python when running just py; otherwise, it will choose the latest version of Python installed.

You can also use #!python2 in a script for it to use that version of Python when double-clicked in Explorer or run without a specific switch (py script.py).

Where is python2 if python points to python3?

4 Answers4