title: Matplotlib import error (expected str, bytes or os.PathLike object, not PosixPath)
body: <p>I'm facing below error while importing matplotlib(version 3.3.2) on ubuntu server.</p>
  <pre><code>  File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
    File &quot;/usr/local/lib/python3.8/site-packages/matplotlib/__init__.py&quot;, line 904, in &lt;module&gt;
      rcParamsDefault = _rc_params_in_file(
    File &quot;/usr/local/lib/python3.8/site-packages/matplotlib/__init__.py&quot;, line 803, in _rc_params_in_file
      with _open_file_or_url(fname) as fd:
    File &quot;/usr/local/lib/python3.8/contextlib.py&quot;, line 113, in __enter__
      return next(self.gen)
    File &quot;/usr/local/lib/python3.8/site-packages/matplotlib/__init__.py&quot;, line 777, in _open_file_or_url
      fname = os.path.expanduser(fname)
    File &quot;/usr/local/lib/python3.8/posixpath.py&quot;, line 231, in expanduser
      path = os.fspath(path)
  TypeError: expected str, bytes or os.PathLike object, not PosixPath
  </code></pre>
  <p>I have tried upgrading to 3.4.1 but still in <code>pip list</code> it is showing as  3.3.2 version.</p>