Check if module exists, if not install it

Question

I want to check if a module exists, if it doesn't I want to install it.

How should I do this?

So far I have this code which correctly prints f if the module doesn't exist.

try:     import keyring except ImportError:     print 'f' 

Answer 1

import pip  def import_or_install(package):     try:         __import__(package)     except ImportError:         pip.main(['install', package])        

This code simply attempt to import a package, where package is of type str, and if it is unable to, calls pip and attempt to install it from there.

Answer 2

Here is how it should be done, and if I am wrong, please correct me. However, Noufal seems to confirm it in another answer to this question, so I guess it's right.

When writing the setup.py script for some scripts I wrote, I was dependent on the package manager of my distribution to install the required library for me.

So, in my setup.py file, I did this:

package = 'package_name' try:     return __import__(package) except ImportError:     return None 

So if package_name was installed, fine, continue. Else, install it via the package manager which I called using subprocess.