code: def get_potential(self, config_nr):
          
          if self.assignments['potentials'] is None:
              self._check_state()
              if self.can_model:
                  self.model(potentials=True)
  
          nids = self.assignments['potentials'][config_nr]
          pot_data = [self.nodeman.nodevals[nid] for nid in nids]
          return pot_data
docs: Return potential data for a given measurement configuration.
  
          Parameters
          ----------
          config_nr: int
              Number of the configurations. Starts at 0
  
          Returns
          -------
          pot_data: list with two numpy.ndarrays
              First array: magnitude potentials, second array: phase potentials