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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 ReportLength(cls, header):
 """Given a header of HeaderLength bytes, calculate the size of this report. Returns: int: The total length of the report including the header that we are passed. """


        parsed_header = cls._parse_header(header)

        auth_size = cls._AUTH_BLOCK_LENGTHS.get(parsed_header.auth_type)
        if auth_size is None:
            raise DataError("Unknown auth block size in BroadcastReport")

        return cls._HEADER_LENGTH + parsed_header.reading_length + auth_size