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How can I manage the modules for python2 when python3 installed as well. In OSX

I'm using OSX and I installed python3 with anaconda installed. In my OSX, there exists two versions of python, i.e. python2 and python3.

I managed the modules in anaconda which only affect modules in python3. But how can I manage(install, delete, update) the modules for python2?

I've checked some posts about 'python2 is at /usr/bin/python' . So it's ok to use python2 by '/usr/bin/python' without configuring alias. But, how can I manage(install, delete, update) the modules for python2 when python3 installed as well. In OSX.

Below is some cmds result. Thank you!!

$ pip --version
pip 18.0 from ~/anaconda/lib/python3.5/site-packages/pip (python 3.5)

$ pip3 -V
pip 18.0 from ~/anaconda/lib/python3.5/site-packages/pip (python 3.5)

$ echo $PATH  
~/anaconda/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/TeX/texbin
Solution

  • Anaconda comes with a package and environment manager called conda. This is what you need to do:

    Create a separate Python 2.7 environment, let's call it old and busted.

    conda create --name old_and_busted python=2.7

    Now switch to this environment:

    conda activate old_and_busted

    Verify it worked if you want:

    python --version

    Install something cool:

    conda install flask

    Bonus, use pip to install something cool in the same environment:

    pip install flask

    What environment are we in again?

    conda env list

    Let's check for that package:

    conda list

    Now this part is very important, make sure to do it often - go back to your Python 3 environment:

    conda activate base

    pipenv manages environments in a similar way. Anaconda specializes in packaging for scientific computing handling packaging non-python extensions (e. g. C, C++) dependencies well.

    ** Note on conda vs source for environment activation **

    If conda activate does not work use source activate. This was changed in Anaconda 4.4.0 Release Notes.

    If you have this in your .bash_profile (or .profile or other magical dotfile) you use source activate:

    export PATH="$HOME/anaconda3/bin:$PATH"

    If you have this updated code in your shell startup then you can use conda activate:

    . $HOME/anaconda3/etc/profile.d/conda.sh conda activate