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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_room_id(self, room_alias):
 """Get room id from its alias. Args: room_alias (str):
 The room alias name. Returns: Wanted room's id. """

        content = self._send("GET", "/directory/room/{}".format(quote(room_alias)))
        return content.get("room_id", None)