code: def version_from_xml_filename(filename):
      "extract the numeric version from the xml filename"
      try:
          filename_parts = filename.split(os.sep)[-1].split('-')
      except AttributeError:
          return None
      if len(filename_parts) == 3:
          try:
              return int(filename_parts[-1].lstrip('v').rstrip('.xml'))
          except ValueError:
              return None
      else:
          return Nonf version_from_xml_filename(filename):
      "extract the numeric version from the xml filename"
      try:
          filename_parts = filename.split(os.sep)[-1].split('-')
      except AttributeError:
          return None
      if len(filename_parts) == 3:
          try:
              return int(filename_parts[-1].lstrip('v').rstrip('.xml'))
          except ValueError:
              return None
      else:
          return None
docs: extract the numeric version from the xml filename