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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 _bind_parse_additional_data(self, key, multiline=False):
 """Returns parsing function which will parse data as text, and add it to the table additional data dictionary with the provided key :param key: dictionary key under which parsed data will be added to table.metadata :type key: str :param multiline: if True this attribute will be treated as multiline :type multiline: bool :return: function with bound key and multiline attributes :rtype: Function """


        def _set_additional_data_bound(self, data):
            """Concrete method for setting additional data
            :param self:
            :type self: OldHEPData
            """
            # if it's multiline, parse it
            if multiline:
                data = self._read_multiline(data)

            if key not in self.additional_data:
                self.additional_data[key] = []
            self.additional_data[key].append(data)

        # method must be bound, so we use __get__
        return _set_additional_data_bound.__get__(self)