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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_duplicate_vals(self, table, column):
 """Retrieve duplicate values in a column of a table."""

        query = 'SELECT {0} FROM {1} GROUP BY {0} HAVING COUNT(*) > 1'.format(join_cols(column), wrap(table))
        return self.fetch(query)