code: def field_exists(self, well_x, well_y, field_x, field_y):
          "Check if field exists ScanFieldArray."
          return self.field(well_x, well_y, field_x, field_y) != Nonf field_exists(self, well_x, well_y, field_x, field_y):
          "Check if field exists ScanFieldArray."
          return self.field(well_x, well_y, field_x, field_y) != None
docs: Check if field exists ScanFieldArray.