title: Pandas Period to to_timestamp giving me TypeError
body: <p>I have a Pandas Dataframe of the format as shown below:</p>
  <pre class="lang-none prettyprint-override"><code>   Month     Count  
     2021-02    100
     2021-03    200  
  </code></pre>
  <p>Where the &quot;Month&quot; column is obtained from a timestamp using <em>dt.to_period('M')</em>.</p>
  <p>Now I have to convert this &quot;Month&quot; column to a fiscal quarter and I have used some approaches to convert the Period to a &quot;datetime&quot; object using &quot;to_timestamp&quot;, but I get the error</p>
  <blockquote>
  <p>TypeError: unsupported Type Int64Index</p>
  </blockquote>
  <p>Is there another way to approach this problem?</p>