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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 row_sparse_data(self, row_id):
 """Returns a copy of the 'row_sparse' parameter on the same context as row_id's. The copy only retains rows whose ids occur in provided row ids. The parameter must have been initialized on this context before. Parameters row_id: NDArray Row ids to retain for the 'row_sparse' parameter. Returns ------- NDArray on row_id's context """

        if self._stype != 'row_sparse':
            raise RuntimeError("Cannot return a copy of Parameter %s via row_sparse_data() " \
                               "because its storage type is %s. Please use data() instead." \
                               %(self.name, self._stype))
        return self._get_row_sparse(self._data, row_id.context, row_id)