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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 current_room_temp(self):
 """Return current room temperature for in-progress session."""

        try:
            rmtemps = self.intervals[0]['timeseries']['tempRoomC']
            num_temps = len(rmtemps)

            if num_temps == 0:
                return None

            rmtemp = rmtemps[num_temps-1][1]
        except KeyError:
            rmtemp = None
        return rmtemp