title: How to comment out a block of Python code in Vim
body: <p>I was wondering if there was any key mapping in Vim to allow me to indent certain lines of code (whether those lines have been selected in visual mode, or <em>n</em> lines above/below current cursor position).</p>
  
  <p>So basically something that converts the following </p>
  
  <pre><code>def my_fun(x, y):
      return x + y
  </code></pre>
  
  <p>to</p>
  
  <pre><code>#def my_fun(x, y):
  #    return x + y
  </code></pre>
  
  <p>I am okay with using either <code>#</code> or <code>"""</code> for commenting out the relevant lines. Ideally, I would also like the same keymapping to uncomment the lines if the given lines have been commented out.</p>