Display python version requirement

[bkestelman]

Environment

• pip version: 18.0
• Python version: 3
• OS: Ubuntu 16.04

Description
When I try to install a package that requires a higher version of python than the one I'm on, it is hard to tell that the error is caused by the python version.

Expected behavior
Pip should clearly state that the package cannot be installed because a different version of python is required. It should also specify which version is required.

How to Reproduce

1. Check that python version is lower than package requirement (e.g. pyenv local <version>)
2. Install package with higher required version than that of environment.
   pip install <package>
   As an example, I used my own package 'edinterface' which requires python 3.6 on an environment running python 3.5.2

Output

  Could not find a version that satisfies the requirement <package> (from versions: )
No matching distribution found for

The required version is not specified. Also, it is not clear if 'version' refers to a python version, pip version, or package version.

[di]

I think this is a duplicate of #5003.

[pradyunsg]

Yep. I agree.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.