casting to list doesn't seem necessary, remain iterator for lazy eval

src/pymatgen/io/vasp/inputs.py

@@ -39,7 +39,7 @@
 from pymatgen.util.typing import Kpoint, Tuple3Floats, Tuple3Ints, Vector3D
 
 if TYPE_CHECKING:
-    from collections.abc import Sequence
+    from collections.abc import Iterator, Sequence
     from typing import Any, ClassVar, Literal
 
     from numpy.typing import ArrayLike
@@ -855,7 +855,7 @@ def from_str(cls, string: str) -> Self:
         Returns:
             Incar object
         """
-        lines: list[str] = list(clean_lines(string.splitlines()))
+        lines: Iterator[str] = clean_lines(string.splitlines())
         params: dict[str, Any] = {}
         for line in lines:
             for sline in line.split(";"):