code: def field_columns(self, well_row, well_column):
          
          imgs = self.well_images(well_row, well_column)
          return list(set([attribute(img, 'x') for img in imgs]))
docs: Field columns for given well. Equivalent to --X in files.
  
          Parameters
          ----------
          well_row : int
              Starts at 0. Same as --V in files.
          well_column : int
              Starts at 0. Same as --U in files.
  
          Returns
          -------
          list of ints
              Columns found for specified well.