title: How to suppress all warnings in window of executable file generated by pyinstaller
body: <p>I have generated an executable file from a python file using pyinstaller. The program works how it is supposed to work but there is this warning message it appears in the window that I would like to hide.</p>
  
  <p>The following line does suppress all warning messages when the python file is run within the IDE.</p>
  
  <pre><code>warnings.filterwarnings('ignore')
  </code></pre>
  
  <p>But in the window of the executable file, this warning is displayed:</p>
  
  <pre><code>\venv\lib\site-packages\PyInstaller\loader\pyimod03_importers.py:627: MatplotlibDeprecationWarning:
  The MATPLOTLIBDATA environment variable was deprecated in Matplotlib 3.1 and will be removed in 3.3.
    exec(bytecode, module.__dict__)
  </code></pre>