Use LazyDataFrame

Signed-off-by: Bram Stoeller <bram.stoeller@alliander.com>

Author: bramstoeller

src/power_grid_model_io/data_stores/csv_dir_store.py

@@ -35,7 +35,7 @@ def load(self) -> TabularData:
         Create a lazy loader for all CSV files in a directory and store them in a TabularData instance.
         """
 
-        def lazy_csv_loader(csv_path: Path) -> Callable[[], pd.DataFrame]:
+        def lazy_csv_loader(csv_path: Path) -> LazyDataFrame:
             def csv_loader():
                 return pd.read_csv(filepath_or_buffer=csv_path, header=self._header_rows, **self._csv_kwargs)