code: def linear_add(self, other, scale_factor=1.0):
          
          if self.structure != other.structure:
              raise ValueError("Adding or subtraction operations can only be "
                               "performed for volumetric data with the exact "
                               "same structure.")
          # To add checks
          data = {}
          for k in self.data.keys():
              data[k] = self.data[k] + scale_factor * other.data[k]
          return VolumetricData(self.structure, data, self._distance_matrix)
docs: Method to do a linear sum of volumetric objects. Used by + and -
          operators as well. Returns a VolumetricData object containing the
          linear sum.
  
          Args:
              other (VolumetricData): Another VolumetricData object
              scale_factor (float): Factor to scale the other data by.
  
          Returns:
              VolumetricData corresponding to self + scale_factor * other.