code: def get_gruneisen_parameter(self, temperature=None, structure=None,
                                  quad=None):
          
          return np.trace(self.get_tgt(temperature, structure, quad)) / 3.
docs: Gets the single average gruneisen parameter from the TGT.
  
          Args:
              temperature (float): Temperature in kelvin, if not specified
                  will return non-cv-normalized value
              structure (float): Structure to be used in directional heat
                  capacity determination, only necessary if temperature
                  is specified
              quad (dict): quadrature for integration, should be
                  dictionary with "points" and "weights" keys defaults
                  to quadpy.sphere.Lebedev(19) as read from file