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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def VerifyStructure(self, parser_mediator, line):
 """Verify that this file is a securityd log file. Args: parser_mediator (ParserMediator):
 mediates interactions between parsers and other components, such as storage and dfvfs. line (str):
 line from a text file. Returns: bool: True if the line is in the expected format, False if not. """

    self._last_month = 0
    self._year_use = parser_mediator.GetEstimatedYear()

    try:
      structure = self.SECURITYD_LINE.parseString(line)
    except pyparsing.ParseException:
      logger.debug('Not a MacOS securityd log file')
      return False

    time_elements_tuple = self._GetTimeElementsTuple(structure)

    try:
      dfdatetime_time_elements.TimeElements(
          time_elements_tuple=time_elements_tuple)
    except ValueError:
      logger.debug(
          'Not a MacOS securityd log file, invalid date and time: {0!s}'.format(
              structure.date_time))
      return False

    self._last_month = time_elements_tuple[1]

    return True