code: def total_weight(self):
          
          weights = self._raw_weights()
          if weights.shape[1] == 0:
              return 0.0
          elif weights.shape[1] < self._ntaps:
              return np.sum(np.mean(weights, axis=1))
          else:
              return self._filter_coeffs.dot(np.sum(weights, axis=0))
docs: Read a weight from the sensor in grams.
  
          Returns
          -------
          weight : float
              The sensor weight in grams.