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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_mapping(self, meta_fields=True):
        '''
        Returns the mapping for the index as a dictionary.

        :param meta_fields: Also include elasticsearch meta fields in the dictionary.
        :return: a dictionary which can be used to generate the elasticsearch index mapping for this doctype.
        '''
        return {'properties': dict((name, field.json()) for name, field in iteritems(self.fields) if meta_fields or name not in AbstractField.meta_fields)}