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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 _recurse_on_row(self, col_dict, nested_value):
 """Apply the schema specified by the given dict to the nested value by recursing on it. Parameters col_dict : dict The schema to apply to the nested value. nested_value : A value nested in a BigQuery row. Returns ------- Union[dict, list] ``dict`` or ``list`` of ``dict`` objects from applied schema. """


        row_value = None

        # Multiple nested records
        if col_dict['mode'] == 'REPEATED' and isinstance(nested_value, list):
            row_value = [self._transform_row(record['v'], col_dict['fields'])
                         for record in nested_value]

        # A single nested record
        else:
            row_value = self._transform_row(nested_value, col_dict['fields'])

        return row_value