Method _validate_encoding

xarray/backends/zarr.py:1452–1459

(self, encoding)

        return ds.drop_vars(ds.indexes)

    def _validate_encoding(self, encoding) -> None:
        if encoding and self._mode in ["a", "a-", "r+"]:
            existing_var_names = self.array_keys()
            for var_name in existing_var_names:
                if var_name in encoding:
                    raise ValueError(
                        f"variable {var_name!r} already exists, but encoding was provided"
                    )


def open_zarr(