title: xlswriter formatting a range
body: <p>In xlswriter, once a format is defined, how can you apply it to a range and not to the whole column or the whole row?</p>
  
  <p>for example:</p>
  
  <pre><code>perc_fmt = workbook.add_format({'num_format': '0.00%','align': 'center'})
  worksheet.set_column('B:B', 10.00, perc_fmt)
  </code></pre>
  
  <p>this gets applied it to the whole "B" column, but how can this "perc_fmt" applied to a range, for example, if I do:</p>
  
  <pre><code>range2 = "B2:C15"
  worksheet2.write(range2, perc_fmt)
  </code></pre>
  
  <p>it says:</p>
  
  <pre><code>TypeError: Unsupported type &lt;class 'xlsxwriter.format.Format'&gt; in write()
  </code></pre>