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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 add_raw(self, length_tag, value_tag):
 """Define the tags used for a private raw data field. :param length_tag: tag number of length field. :param value_tag: tag number of value field. Data fields are not terminated by the SOH character as is usual for FIX, but instead have a second, preceding field that specifies the length of the value in bytes. The parser is initialised with all the data fields defined in FIX.5.0, but if your application uses private data fields, you can add them here, and the parser will process them correctly. """


        self.raw_len_tags.append(length_tag)
        self.raw_data_tags.append(value_tag)
        return