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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 get_type(self):
 """ Returns serialization type of binary form. :return: Serialization type of binary form. """

        if self.total_size() == 0:
            return CONSTANT_TYPE_NULL
        return unpack_from(FMT_BE_INT, self._buffer, TYPE_OFFSET)[0]