title: brew install graphviz - [#<Dependency: "python" []>, #<Options: []>] cannot be installed as binary package and must be built from source
body: <p>When I try to write <code>brew install graphviz</code> in the terminal the error is </p>
  
  <pre><code>Error: The following formula
    [#Dependency: "python" []&gt;, #&lt;Options: []&gt;]
  cannot be installed as binary package and must be built from source.
  Install the Command Line Tools:
    xcode-select --install
  </code></pre>
  
  <p>I tried already <code>xcode-select --install</code> with the result:</p>
  
  <blockquote>
    <p>"xcode-select: note: install requested for command line developer tools"</p>
  </blockquote>