code: def dry_lapse(pressure, temperature, ref_pressure=None):
      r
      if ref_pressure is None:
          ref_pressure = pressure[0]
      return temperature * (pressure / ref_pressure)**mpconsts.kappa
docs: r"""Calculate the temperature at a level assuming only dry processes.
  
      This function lifts a parcel starting at `temperature`, conserving
      potential temperature. The starting pressure can be given by `ref_pressure`.
  
      Parameters
      ----------
      pressure : `pint.Quantity`
          The atmospheric pressure level(s) of interest
      temperature : `pint.Quantity`
          The starting temperature
      ref_pressure : `pint.Quantity`, optional
          The reference pressure. If not given, it defaults to the first element of the
          pressure array.
  
      Returns
      -------
      `pint.Quantity`
         The resulting parcel temperature at levels given by `pressure`
  
      See Also
      --------
      moist_lapse : Calculate parcel temperature assuming liquid saturation
                    processes
      parcel_profile : Calculate complete parcel profile
      potential_temperature