title: Openpyxl: How to merge cells using variable rows
body: <p>I can't figure out how to merge cells without using the format 'A1:A4'</p>
  
  <p>I want to be able to use ws.cell(row=x,column=y) format to set the start and end points of the merge.</p>
  
  <p>The code below demonstrates what I want, but doesn't work as the range argument isn't in the correct format.</p>
  
  <pre class="lang-py prettyprint-override"><code>for x in range(10):
      start = ws.cell(row=x,column=1)
      end = ws.cell(row=x, column=4)
      ws.merge_cells(start:end)
  </code></pre>
  
  <p>Any help much appreciated!</p>