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ModuleNotFoundError on virtual environment

After installing miniconda, my python modules stopped working, throwing ModuleNotFoundError. From what I can tell, miniconda changed my default environment settings. I checked both .bash_profile and .bashrc and updated the files to give conda the lowest priority. This fixed my default python version but didn't fix any of the broken modules.
Next I checked my PYTHONPATH with python3 -c "import sys;print(sys.path)". I discovered that the PYTHONPATH consisted entirely of conda python paths instead of the python version I had called. For reference, my default python version should be 3.8 (now set in .bashrc), and the conda version is 3.9.
['', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python39.zip', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/lib-dynload']
I then manually changed my PYTHONPATH in the .bashrc file to include the appropriate library paths. After reloading .bashrc:
['', '/Users/Ghoti/venv/3.8/lib/python3.8/site-packages', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.8/lib/python3.8/site-packages', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python39.zip', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9', '/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/lib-dynload']
My modules now work! However, I haven't been able to figure out how to stop the conda 3.9 libraries from being appended to my PYTHONPATH. In addition, my printed python version is wrong.
Ghoti$ python --version
Python 3.9.6
Ghoti$ which python
/Users/Ghoti/venv/3.8/bin/python
I was able to "fix" my ModuleNotFoundError problem. However, the solution is only temporary. If I ever need to switch python version/environment, I'll have to go through the process again. I'd like to figure out what is overriding my PYTHONPATH, causing it to call conda 3.9 libraries, and fix the python version irregularity. I've considered that there might be a script/process running in the background, but I haven't found any related to conda/miniconda. I've also been looking for a python setting/config file. No luck. Any suggestions on where I should look?
Edit - Did some more digging. It looks like my version 3.8 python executable was entirely overwritten, and the only existing python installation that is version 3.9.6 is in my "/usr/bin". The two conda environments have versions "3.9.12" and "3.8.13". I feel more confident the issue isn't due to conda, but unsure what could have caused the problem.
Final Edit
I don't think the problem was miniconda. I did start having problems within a few days of using miniconda and I original assumed that it just took me a while to notice the issues. However, I now think that my virtual environment was created using a shared python. Problems were noticed on the same day that I connected to network. The shared python version changed, and that broke my environment. I don't have a solution to salvage the broken environment, but rebuilding it from scratch shouldn't take too long.

Sounds like you only want to use conda when you explicitly need it, in other words, the default Python is the system Python.
If that's the case, you should disable the auto-activation of the base environment:
conda config --set auto_activate_base false
<restart shell>
Now you'll need to explicitly activate the conda environment before you can use the conda Python:
$ python
Python 3.10.6 (main, Aug 11 2022, 13:49:25) [Clang 13.1.6 (clang-1316.0.21.2.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
$ conda activate base
(base) $ python
Python 3.9.12 (main, Jun 1 2022, 06:36:29)
[Clang 12.0.0 ] :: Anaconda, Inc. on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

terminal runs python 2.7 when I have python 3.5 installed on mac.

I was installing, uninstalling and reinstalling pythons on my mac,
and I think things are screwed up a little.
At first by default, terminal ran Python 3.5 when I typed
$python
, but after doing some things, it installed 2.7 and now the terminal runs python 2.7 instead of 3.5
I installed python 3.5 form http://python.org/.
When I open up bash_profile
$vim ~/.bash_profile
This is what shows up
# virtualenv
export WORKON_HOME=~/.virtualenvs
source /usr/local/bin/virtualenvwrapper.sh
# Setting PATH for Python 3.5
# The orginal version is saved in .bash_profile.pysave
PATH="/Library/Frameworks/Python.framework/Versions/3.5/bin:${PATH}"
export PATH
Now when I type:
$ python
This shows up:
Python 2.7.11 (default, Jun 23 2016, 17:25:20)
[GCC 4.2.1 Compatible Apple LLVM 7.3.0 (clang-703.0.31)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
How can I reset all the python stuff(remove older versions, etc) to the factory version that i had when I first bought Mac(python3.5)?

This worked for me:
Python 3.x
python3
Python 2.x
python
in terminal

To see what command is actually going to run when you type python at the prompt, check the top result of:
type -a python
This will list any aliases as well as taking into account the full PATH definition. To figure out why python 2 is getting precedence over python 3, be sure to check your ~/.bashrc file if it exists as well as your ~/.bash_profile.

To check your Python binaries, run:
$ which -a python python2 python3
Then check which python path comes first.
Then either set your $PATH or $PYTHONPATH (then reload your shell), or use python2 or python3 command instead.
You can also use following workaround:
PATH="/usr/bin:$PATH" ./python_script.py
where /usr/bin is pointing to the right Python binary.

Installed Python from Package, Terminal didn't update?

Terminal is still showing Python 2.7.2 after an install of 3.3.0
I'm new to python- just want to get a good development environment working on Mac 10.8.

Use python3 instead of python:
$ python3
Python 3.2.3 (default, Oct 19 2012, 19:53:57)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.

See PEP 394:
This PEP provides a convention to ensure that Python scripts can continue to be portable across *nix systems, regardless of the default version of the Python interpreter (i.e. the version invoked by the python command).
python2 will refer to some version of Python 2.x
python3 will refer to some version of Python 3.x
python should refer to the same target as python2 but may refer to python3 on some bleeding edge distributions
You have Python 2 and Python 3 installed, so the python command refers to python2. If you want Python 3, do it explicitly with the python3 command.

You have few options
In your bash ~/.bash_profile add alias python='python3'
Instead of using python command use python3 instead.
Install python3 via homebrew

python 2 instead of python 3 as the (temporary) default python?

on my computer
~$ python -V
Python 3.2.1
but I get into problems when I run some python programs. my guess is (or at least I want to try this) that there is some backward compatibility issues, and I want to run those python scripts with
python2 2.7.2-2
which is also installed on my system but I do not know how to make it as the (temporary) default python. The python script starts with
#!/usr/bin/env python
and I am using arch linux.

You can use virtualenv
# Use this to create your temporary python "install"
# (Assuming that is the correct path to the python interpreter you want to use.)
virtualenv -p /usr/bin/python2.7 --distribute temp-python
# Type this command when you want to use your temporary python.
# While you are using your temporary python you will also have access to a temporary pip,
# which will keep all packages installed with it separate from your main python install.
# A shorter version of this command would be ". temp-python/bin/activate"
source temp-python/bin/activate
# When you no longer wish to use you temporary python type
deactivate
Enjoy!

mkdir ~/bin
PATH=~/bin:$PATH
ln -s /usr/bin/python2 ~/bin/python
To stop using python2, exit or rm ~/bin/python.

Just call the script using something like python2.7 or python2 instead of just python.
So:
python2 myscript.py
instead of:
python myscript.py
What you could alternatively do is to replace the symbolic link "python" in /usr/bin which currently links to python3 with a link to the required python2/2.x executable. Then you could just call it as you would with python 3.

You don't want a "temporary default Python"
You want the 2.7 scripts to start with
/usr/bin/env python2.7
And you want the 3.2 scripts to begin with
/usr/bin/env python3.2
There's really no use for a "default" Python. And the idea of a "temporary default" is just a road to absolute confusion.
Remember.
Explicit is better than Implicit.

You could use alias python="/usr/bin/python2.7":
bash-3.2$ alias
bash-3.2$ python
Python 2.7.6 (v2.7.6:3a1db0d2747e, Nov 10 2013, 00:42:54)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> ^D
bash-3.2$ alias python="/usr/bin/python3.3"
bash-3.2$ python
Python 3.3.3 (v3.3.3:c3896275c0f6, Nov 16 2013, 23:39:35)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

If you have some problems with virtualenv,
You can use it:
sudo ln -sf python2 /usr/bin/python
and
sudo ln -sf python3 /usr/bin/python

Use python command to launch scripts, not shell directly. E.g.
python2 /usr/bin/command
AFAIK this is the recommended method to workaround scripts with bad env interpreter line.

As an alternative to virtualenv, you can use anaconda.
On Linux, to create an environment with python 2.7:
conda create -n python2p7 python=2.7
source activate python2p7
To deactivate it, you do:
source deactivate
It is possible to install other package inside your environment.

I think it is easier to use update-alternatives:
sudo update-alternatives --install /usr/bin/python python /usr/bin/python2.7 1

python location on mac osx

I'm a little confused with the python on osx. I do not know if the previous owner of the laptop has installed macpython using macport. And I remembered that osx has an builtin version of python. I tried using type -a python and the result returned
python is /usr/bin/python
python is /usr/local/bin/python
However running both python at these locations give me [GCC 4.2.1 (Apple Inc. build 5646)] on darwin. Do they both refer to the same builtin python mac provided?
I also read that installing macpython one would
A MacPython 2.5 folder in your Applications folder. In here you
find IDLE, the development environment that is a standard part of
official Python distributions...
I looked at Applications, and theres a MacPort folder with python2.6 and the mentioned stuff in it. But running IDLE, i find the same message as above.
Hmm I'm a little confused. Which is which?

This one will solve all your problems not only on Mac but
to find it on Linux also ( & every basic shell).
TL;DR (you don't have to go through all the answer - just the 1st half).
LET'S GO
Run in terminal:
which python3
On Mac you should get:
/usr/local/bin/python3
WAIT!!! It's prob a symbolic link, how do you know? Run:
ls -al /usr/local/bin/python3
and you'll get (if you've installed Python w/ Brew):
/usr/local/bin/python3 -> /usr/local/Cellar/python/3.6.4_4/bin/python3
which means that your
/usr/local/bin/python3
is actually pointing to (the real location)
/usr/local/Cellar/python/3.6.4_4/bin/python3
That's it!
Longer version (optional):
If for some reason, your
/usr/local/bin/python3
is not pointing to the place you want, which in our case:
/usr/local/Cellar/python/3.6.4_4/bin/python3
just back it up (+cool trick to add .orig suffix to file):
cp /usr/local/bin/python3{,.orig}
and run:
rm -rf /usr/local/bin/python3
now create a new symbolic link:
ln -s /usr/local/Cellar/python/3.6.4_4/bin/python3 /usr/local/bin/python3
and now your
/usr/local/bin/python3
is pointing to
/usr/local/Cellar/python/3.6.4_4/bin/python3
Check it out by running:
ls -al /usr/local/bin/python3

I found the easiest way to locate it, you can use
which python
it will show something like this:
/usr/bin/python

[GCC 4.2.1 (Apple Inc. build 5646)] is the version of GCC that the Python(s) were built with, not the version of Python itself. That information should be on the previous line. For example:
# Apple-supplied Python 2.6 in OS X 10.6
$ /usr/bin/python
Python 2.6.1 (r261:67515, Jun 24 2010, 21:47:49)
[GCC 4.2.1 (Apple Inc. build 5646)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
# python.org Python 2.7.2 (also built with newer gcc)
$ /usr/local/bin/python
Python 2.7.2 (v2.7.2:8527427914a2, Jun 11 2011, 15:22:34)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
Items in /usr/bin should always be or link to files supplied by Apple in OS X, unless someone has been ill-advisedly changing things there. To see exactly where the /usr/local/bin/python is linked to:
$ ls -l /usr/local/bin/python
lrwxr-xr-x 1 root wheel 68 Jul 5 10:05 /usr/local/bin/python# -> ../../../Library/Frameworks/Python.framework/Versions/2.7/bin/python
In this case, that is typical for a python.org installed Python instance or it could be one built from source.

On Mac OS X, it's in the Python framework in /System/Library/Frameworks/Python.framework/Resources.
Full path is:
/System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python
Btw it's easy to find out where you can find a specific binary: which Python will show you the path of your Python binary (which is probably the same as I posted above).

I checked a few similar discussions and found out the best way to locate all python2/python3 builds is:
which -a python python3

On High Sierra
which python
shows the default python but if you downloaded and installed the latest version from python.org you can find it by:
which python3.6
which on my machine shows
/Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6

installed with 'brew install python3', found it here

Run this in your interactive terminal
import os
os.path
It will give you the folder where python is installed

i found it here:
/Library/Frameworks/Python.framework/Versions/3.6/bin

which python3 simply result in a path in which the interpreter settles down.

run the following code in a .py file:
import sys
print(sys.version)
print(sys.executable)

I have a cook recipe for finding things in linux/macos
First update the locate db then do a
locate WHATiWANTtoSEARCH | less
do a /find to find what you are looking for.
to update your locate db in macos do this:
sudo /usr/libexec/locate.updatedb
it sometimes takes a while. Hope this helps :)