====== Version Mismatch in Python Package ======

I recently encountered a problem while I was trying to use Astropy v3.1.2.  It was complaining about my Numpy version:

<code>
Traceback (most recent call last):
  File "./body-local.py", line 3, in <module>
    from astropy.time import Time
  File "/home/jimc/.local/lib/python3.6/site-packages/astropy/__init__.py", line 121, in <module>
    _check_numpy()
  File "/home/jimc/.local/lib/python3.6/site-packages/astropy/__init__.py", line 115, in _check_numpy
    raise ImportError(msg)
ImportError: Numpy version 1.13.0 or later must be installed to use Astropy
</code>

The strange part?  When I checked my Numpy version, it reported 1.16.2. :-\

After a bit of digging, I discovered that this behavior can occur when you have multiple versions of the same package installed.  This can happen when you install a package globally //and// locally, or when packages are installed by other processes.  In any case, the solution was this:

First, repeatedly uninstall the offending package until no more installations are found:

<code bash>
pip3 uninstall numpy
sudo pip3 uninstall numpy
</code>

Then, reinstall:

<code bash>
sudo pip3 install numpy
</code>

{{tag>python}}