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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 add(self, other_op):
 """Combines `other_op` with the operation held by this aggregator. N.B. It merges the operations log entries and metric values, but makes the assumption the operation is consistent. It's the callers responsibility to ensure consistency Args: other_op ( class:`endpoints_management.gen.servicecontrol_v1_messages.Operation`):
 an operation merge into this one """

        self._op.logEntries.extend(other_op.logEntries)
        self._merge_timestamps(other_op)
        self._merge_metric_values(other_op)