title: Applying conditional formatting to non-contiguous selections in openpyxl
body: <p>In Excel, I can make multiple selections on a spreadsheet, and use conditional formatting to apply a color scale which includes all of my selections.</p>
  
  <p>With openpyxl, in order to apply conditional formatting, I need a range string:</p>
  
  <pre><code>rule = ColorScaleRule(start_type="min", start_color="FFFFFF", 
                        end_type="max", end_color="247CBD")
  range_string = "A1:D10"
  worksheet.conditional_formatting.add(range_string, rule)
  </code></pre>
  
  <p>If I try to use a range string to select non-contiguous areas using the normal Excel notation, eg:</p>
  
  <pre><code>range_string = "A1:D10,A20:D30"
  </code></pre>
  
  <p>then the format does not get applied, the cells remain unformatted.</p>
  
  <p>Does anyone know how to accomplish this?</p>