Update skew_heap.py

Author: lighting9999

data_structures/heap/skew_heap.py

@@ -13,7 +13,7 @@ def __lt__(self, other: object) -> bool: ...
 T = TypeVar("T", bound=Comparable)
 
 
-class SkewNode(Generic[T]):
+class SkewNode[T]:
     """
     One node of the skew heap. Contains the value and references to
     two children.
@@ -90,7 +90,7 @@ def _is_less_than(a: T, b: T) -> bool:
             return str(a) < str(b)
 
 
-class SkewHeap(Generic[T]):
+class SkewHeap[T]:
     """
     A data structure that allows inserting a new value and popping the smallest
     values. Both operations take O(logN) time where N is the size of the heap.