title: Grouping data on column value
body: <p>Hi I have data (in excel and text file as well) like </p>
  
  <pre><code>C1   C2    C3
   1    p     a
   1    q     b
   2    r     c
   2    s     d
  </code></pre>
  
  <p>And I want the output like:</p>
  
  <pre><code>C1   C2   C3
   1   p,q  a,b
   2   r,s  c,d
  </code></pre>
  
  <p>How can I group the data based on column values.
  I am open to anything: any library, any language, any tool
  Like python, bash, or even excel?</p>
  
  <p>I think we can do this using pandas in python, but I havent used it before.</p>
  
  <p>Any leads appreciated.</p>