Remove some redundant empty lines from dataset.py which codecov is …

…counting as untested

src/metatensor/models/utils/data/dataset.py

@@ -9,7 +9,8 @@
 
 
 class Dataset:
-    """A version of the `metatensor.learn.Dataset` class that allows for
+    """
+    A version of the `metatensor.learn.Dataset` class that allows for
     the use of `mtm::` prefixes in the keys of the dictionary. See
     https://github.com/lab-cosmo/metatensor/issues/621.
 
@@ -20,22 +21,18 @@ class Dataset:
     """
 
     def __init__(self, dict: Dict):
-
         new_dict = {}
         for key, value in dict.items():
             key = key.replace("mtm::", "mtm_")
             new_dict[key] = value
-
         self.mts_learn_dataset = metatensor.learn.Dataset(**new_dict)
 
     def __getitem__(self, idx: int) -> Dict:
-
         mts_dataset_item = self.mts_learn_dataset[idx]._asdict()
         new_dict = {}
         for key, value in mts_dataset_item.items():
             key = key.replace("mtm_", "mtm::")
             new_dict[key] = value
-
         return new_dict
 
     def __len__(self) -> int:
@@ -99,7 +96,6 @@ def get_all_species(datasets: Union[Dataset, List[Dataset]]) -> List[int]:
     # Remove duplicates and sort:
     result = list(set(species))
     result.sort()
-
     return result