code: def concatenate(self, other):
          
          if not isinstance(other, LineString):
              other = LineString(other)
          return self.deepcopy(
              coords=np.concatenate([self.coords, other.coords], axis=0))
docs: Concatenate this line string with another one.
  
          This will add a line segment between the end point of this line string
          and the start point of `other`.
  
          Parameters
          ----------
          other : imgaug.augmentables.lines.LineString or ndarray \
                  or iterable of tuple of number
              The points to add to this line string.
  
          Returns
          -------
          imgaug.augmentables.lines.LineString
              New line string with concatenated points.
              The `label` of this line string will be kept.