title: custom data sorting(alphabetic+integer) in pandas dataframe
body: <p>I have a dataframe where I need to sort the contents of one column (comma separated) (alphabetically + Numberic) :</p>
  <p>Input : -</p>
  <pre><code>      Invoice Number
  0     IN-2
  1     IN-1
  2     IN-5
  3     IN-20
  4     IN-10
  </code></pre>
  <p>I want output like</p>
  <pre><code>      Invoice Number
  0     IN-1
  1     IN-2
  2     IN-5
  3     IN-10
  4     IN-20
  </code></pre>
  <p>I tried</p>
  <blockquote>
  <p>df.sort_values(by=['Invoice Number'])</p>
  </blockquote>
  <p>But it sorted :</p>
  <pre><code>      Invoice Number
  0     IN-1
  1     IN-10
  2     IN-2
  3     IN-20
  4     IN-5
  </code></pre>
  <p>If anybody know how to sort my data (alphabetic+integer) value so tell me.</p>