docs: def set_field(self, target, rate, wait_for_stability=True):
          """Sets the field to the specified value.
          
          :param field: The target field in Tesla.
          :param rate: The field rate in tesla per minute.
          :param wait_for_stability: If True, the function call blocks until the
              target field is reached.
          
          """
          self.field.target = target
          self.field.sweep_rate = rate
          self.activity = 'to setpoint'
          while self.status['mode'] != 'at rest':
              time.sleep(1)