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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_oplog_cursor(self, timestamp=None):
 """Get a cursor to the oplog after the given timestamp, excluding no-op entries. If no timestamp is specified, returns a cursor to the entire oplog. """

        query = {"op": {"$ne": "n"}}
        if timestamp is None:
            cursor = self.oplog.find(query, cursor_type=CursorType.TAILABLE_AWAIT)
        else:
            query["ts"] = {"$gte": timestamp}
            cursor = self.oplog.find(
                query, cursor_type=CursorType.TAILABLE_AWAIT, oplog_replay=True
            )
        return cursor