Try again

a2c_ase/soft_sphere.py

@@ -136,7 +136,7 @@ def __init__(self, **kwargs: Any) -> None:
     def calculate(
         self,
         atoms: Optional[Atoms] = None,
-        properties: list[str] | None = None,
+        properties: Optional[list[str]] = None,
         system_changes: list[str] = all_changes,
     ) -> None:
         """Calculate the energy, forces and stress of the system.