docs: def last_bed_temp(self):
          """Return avg bed temperature for last session."""
          try:
              bedtemps = self.intervals[1]['timeseries']['tempBedC']
          except KeyError:
              return None
          tmp = 0
          num_temps = len(bedtemps)
  
          if num_temps == 0:
              return None
  
          for temp in bedtemps:
              tmp += temp[1]
          bedtemp = tmp/num_temps
          return bedtemp