code: def _Backward3_T_Ps(P, s):
      
      sc = 4.41202148223476
      if s <= sc:
          T = _Backward3a_T_Ps(P, s)
      else:
          T = _Backward3b_T_Ps(P, s)
      return T
docs: Backward equation for region 3, T=f(P,s)
  
      Parameters
      ----------
      P : float
          Pressure, [MPa]
      s : float
          Specific entropy, [kJ/kgK]
  
      Returns
      -------
      T : float
          Temperature, [K]