title: Problem with installation of matplotlib in Python
body: <p>I am trying to install matplotlib in windows x64 with python 3.9.
  When I do:</p>
  <blockquote>
  <p>pip install matplotlib</p>
  </blockquote>
  <p>I get this error:</p>
  <pre><code>ERROR: Command errored out with exit status 1:
   command: 'c:\program files\python39\python.exe' -c 'import sys, setuptools, tokenize; sys.argv[0] = '&quot;'&quot;'C:\\Users\\Luca\\AppData\\Local\\Temp\\pip-install-zlfu5f08\\kiwisolver\\setup.py'&quot;'&quot;'; __file__='&quot;'&quot;'C:\\Users\\Luca\\AppData\\Local\\Temp\\pip-install-zlfu5f08\\kiwisolver\\setup.py'&quot;'&quot;';f=getattr(tokenize, '&quot;'&quot;'open'&quot;'&quot;', open)(__file__);code=f.read().replace('&quot;'&quot;'\r\n'&quot;'&quot;', '&quot;'&quot;'\n'&quot;'&quot;');f.close();exec(compile(code, __file__, '&quot;'&quot;'exec'&quot;'&quot;'))' egg_info --egg-base 'C:\Users\Luca\AppData\Local\Temp\pip-pip-egg-info-mriih1bh'
       cwd: C:\Users\Luca\AppData\Local\Temp\pip-install-zlfu5f08\kiwisolver\
  Complete output (44 lines):
  WARNING: The wheel package is not available.
    ERROR: Command errored out with exit status 1:
     command: 'c:\program files\python39\python.exe' -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '&quot;'&quot;'C:\\Users\\Luca\\AppData\\Local\\Temp\\pip-wheel-pvxhkv11\\cppy\\setup.py'&quot;'&quot;'; __file__='&quot;'&quot;'C:\\Users\\Luca\\AppData\\Local\\Temp\\pip-wheel-pvxhkv11\\cppy\\setup.py'&quot;'&quot;';f=getattr(tokenize, '&quot;'&quot;'open'&quot;'&quot;', open)(__file__);code=f.read().replace('&quot;'&quot;'\r\n'&quot;'&quot;', '&quot;'&quot;'\n'&quot;'&quot;');f.close();exec(compile(code, __file__, '&quot;'&quot;'exec'&quot;'&quot;'))' bdist_wheel -d 'C:\Users\Luca\AppData\Local\Temp\pip-wheel-1s8s6o5r'
         cwd: C:\Users\Luca\AppData\Local\Temp\pip-wheel-pvxhkv11\cppy\
    Complete output (6 lines):
    usage: setup.py [global_opts] cmd1 [cmd1_opts] [cmd2 [cmd2_opts] ...]
       or: setup.py --help [cmd1 cmd2 ...]
       or: setup.py --help-commands
       or: setup.py cmd --help
  
    error: invalid command 'bdist_wheel'
    ----------------------------------------
    ERROR: Failed building wheel for cppy
  ERROR: Failed to build one or more wheels
  Traceback (most recent call last):
    File &quot;c:\program files\python39\lib\site-packages\setuptools\installer.py&quot;, line 128, in fetch_build_egg
      subprocess.check_call(cmd)
    File &quot;c:\program files\python39\lib\subprocess.py&quot;, line 373, in check_call
      raise CalledProcessError(retcode, cmd)
  subprocess.CalledProcessError: Command '['c:\\program files\\python39\\python.exe', '-m', 'pip', '--disable-pip-version-check', 'wheel', '--no-deps', '-w', 'C:\\Users\\Luca\\AppData\\Local\\Temp\\tmpggz7lusd', '--quiet', 'cppy&gt;=1.1.0']' returned non-zero exit status 1.
  
  The above exception was the direct cause of the following exception:
  
  Traceback (most recent call last):
    File &quot;&lt;string&gt;&quot;, line 1, in &lt;module&gt;
    File &quot;C:\Users\Luca\AppData\Local\Temp\pip-install-zlfu5f08\kiwisolver\setup.py&quot;, line 59, in &lt;module&gt;
      setup(
    File &quot;c:\program files\python39\lib\site-packages\setuptools\__init__.py&quot;, line 164, in setup
      _install_setup_requires(attrs)
    File &quot;c:\program files\python39\lib\site-packages\setuptools\__init__.py&quot;, line 159, in _install_setup_requires
      dist.fetch_build_eggs(dist.setup_requires)
    File &quot;c:\program files\python39\lib\site-packages\setuptools\dist.py&quot;, line 699, in fetch_build_eggs
      resolved_dists = pkg_resources.working_set.resolve(
    File &quot;c:\program files\python39\lib\site-packages\pkg_resources\__init__.py&quot;, line 779, in resolve
      dist = best[req.key] = env.best_match(
    File &quot;c:\program files\python39\lib\site-packages\pkg_resources\__init__.py&quot;, line 1064, in best_match
      return self.obtain(req, installer)
    File &quot;c:\program files\python39\lib\site-packages\pkg_resources\__init__.py&quot;, line 1076, in obtain
      return installer(requirement)
    File &quot;c:\program files\python39\lib\site-packages\setuptools\dist.py&quot;, line 758, in fetch_build_egg
      return fetch_build_egg(self, req)
    File &quot;c:\program files\python39\lib\site-packages\setuptools\installer.py&quot;, line 130, in fetch_build_egg
      raise DistutilsError(str(e)) from e
  distutils.errors.DistutilsError: Command '['c:\\program files\\python39\\python.exe', '-m', 'pip', '--disable-pip-version-check', 'wheel', '--no-deps', '-w', 'C:\\Users\\Luca\\AppData\\Local\\Temp\\tmpggz7lusd', '--quiet', 'cppy&gt;=1.1.0']' returned non-zero exit status 1.
  ----------------------------------------ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.
  </code></pre>
  <p>I tried to follow all of advice that i found here, but it continues to generate the error.</p>
  <p>Who can help me, please?</p>