code: def read_excel_file(inputfile, sheet_name):
      
      workbook = xlrd.open_workbook(inputfile)
      output = []
      found = False
      for sheet in workbook.sheets():
          if sheet.name == sheet_name:
              found = True
              for row in range(sheet.nrows):
                  values = []
                  for col in range(sheet.ncols):
                      values.append(sheet.cell(row, col).value)
                  output.append(values)
      if not found:  # pragma: no cover
          raise MQ2Exception('Invalid session identifier provided')
      return output
docs: Return a matrix containing all the information present in the
      excel sheet of the specified excel document.
  
      :arg inputfile: excel document to read
      :arg sheetname: the name of the excel sheet to return