I have a Mac with OS 10.11.4, which has both Python 2.7.3 (OS Build-in) and Python 3.5.1 (just installed). With Python2, I can import Biopython (version 1.61). The Python3, however, cannot see the Biopython package. I want to update Biopython to the latest version 1.66 and link it to Python3. Do I need to uninstall version 1.61 first? Is yes, how? How to make sure the installation from tarball will link it to Python3? Thanks.
This is somewhat off-topic for the site, but if you `pip3 install --user biopython` it'll install the most recent version of biopython. Packages are always specific to a version of python, so your python2 and python3 installed versions can coexist.