title: UserWarning: "Cannot parse header or footer so it will be ignored" on loading xlsm file
body: <p>Trying to open xlsm file using python</p>
  
  <p>Below is the code :</p>
  
  <pre><code>import libraries
  import openpyxl
  from openpyxl import load_workbook
  from openpyxl import Workbook
  from openpyxl.styles import colors
  from openpyxl.styles import Color, PatternFill, Font, Border
  
  #path of the source sheet
  path = "C:\DATA\PYTHON\Practise\SysTSAutSW300PFCRebuildDemo.xlsm"
  wb1 = load_workbook(path)
  
  sheet = wb1.get_sheet_by_name('PFC_Rebuild')
  
  celldata = sheet['L33']
  
  print celldata
  </code></pre>
  
  <p>It gives the below error :</p>
  
  <blockquote>
    <p>Warning (from warnings module):   File
    "C:\Python27\lib\site-packages\openpyxl\worksheet\header_footer.py",
    line 49
        warn("""Cannot parse header or footer so it will be ignored""") UserWarning: Cannot parse header or footer so it will be ignored</p>
  </blockquote>