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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 an IIS 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 was successfully parsed. """

    # TODO: self._line_structures is a work-around and this needs
    # a structural fix.
    self._line_structures = self.LINE_STRUCTURES

    self._day_of_month = None
    self._month = None
    self._year = None

    # TODO: Examine other versions of the file format and if this parser should
    # support them. For now just checking if it contains the IIS header.
    if self._SIGNATURE in line:
      return True

    return False