code: def fan_maxcfm(ddtt):
      
      if str(ddtt.Maximum_Flow_Rate).lower() == 'autosize':
      # str can fail with unicode chars :-(
          return 'autosize'
      else:
          m3s = float(ddtt.Maximum_Flow_Rate)
          return m3s2cfm(m3s)
docs: return the fan max cfm