title: brew install ffmpeg installs python 3.9
body: <p>For some reason <code>brew install ffmpeg</code> downloads python 3.9 as dependence</p>
  <pre><code>==&gt; Installing dependencies for ffmpeg: gnutls, python@3.9, glib, cairo, gobject-introspection, harfbuzz, libass and libvpx
  </code></pre>
  <p>As I can see here <a href="https://formulae.brew.sh/formula/ffmpeg" rel="nofollow noreferrer">https://formulae.brew.sh/formula/ffmpeg</a> there is no dependence on python 3.9</p>
  <p>How can I install ffmpeg for my current python Python 3.7.7?</p>
  <p><strong>Update:</strong></p>
  <p>Maybe something is broken in my python installation?</p>
  <pre><code>brew info python
  
  python@3.9: stable 3.9.0 (bottled)
  Interpreted, interactive, object-oriented programming language
  https://www.python.org/
  /usr/local/Cellar/python/3.7.7 (4,165 files, 64.0MB) *
    Poured from bottle on 2020-04-03 at 20:11:58
  From: https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/python@3.9.rb
  License: Python-2.0
  ==&gt; Dependencies
  Build: pkg-config ✔
  Required: gdbm ✔, openssl@1.1 ✔, readline ✔, sqlite ✔, xz ✔
  ==&gt; Caveats
  Python has been installed as
    /usr/local/bin/python3
  
  Unversioned symlinks `python`, `python-config`, `pip` etc. pointing to
  `python3`, `python3-config`, `pip3` etc., respectively, have been installed into
    /usr/local/opt/python@3.9/libexec/bin
  
  You can install Python packages with
    pip3 install &lt;package&gt;
  They will install into the site-package directory
    /usr/local/lib/python3.9/site-packages
  
  See: https://docs.brew.sh/Homebrew-and-Python
  ==&gt; Analytics
  install: 588,344 (30 days), 666,372 (90 days), 666,373 (365 days)
  install-on-request: 104,126 (30 days), 105,703 (90 days), 105,705 (365 days)
  build-error: 0 (30 days)
  </code></pre>
  <p><code>brew info</code> shows <code>python@3.9</code> but actually it's 3.7.7:</p>
  <pre><code>/usr/local/bin/python3 -V
  Python 3.7.7
  </code></pre>