message: Made error message in keras.backend.bias_add match check
diff: @@ -6004,7 +6004,7 @@ def bias_add(x, bias, data_format=None):
  if len(bias_shape) != 1 and len(bias_shape) != ndim(x) - 1:
  raise ValueError(
  'Unexpected bias dimensions %d, expect to be 1 or %d dimensions' %
  - (len(bias_shape), ndim(x)))
  + (len(bias_shape), ndim(x) - 1))
  if len(bias_shape) == 1:
  if data_format == 'channels_first':
  