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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 _multi_value_field(self, field):
 """ Private method that returns `True` if a field is multi-valued, else `False`. Required arguemnts: `field` -- The field to lookup Returns a boolean value indicating whether the field is multi-valued. """

        for field_dict in self.schema:
            if field_dict['field_name'] == field:
                return field_dict['multi_valued'] == 'true'
        return False