[networkx] Accept any node type in graph functions that took Graph[Hashable] (#16557)

Graph is invariant in its node type, so Graph[Hashable] rejected
Graph[str] and similar graphs. Use the _Node type variable, like the
other functions in the module.

Author: cristianchiriac

stubs/networkx/networkx/classes/function.pyi

@@ -1,5 +1,5 @@
 from _typeshed import Incomplete, SupportsItems, SupportsKeysAndGetItem, Unused
-from collections.abc import Callable, Collection, Generator, Hashable, Iterable, Iterator
+from collections.abc import Callable, Collection, Generator, Iterable, Iterator
 from typing import Literal, TypeVar, overload
 
 from networkx import _dispatchable
@@ -63,11 +63,11 @@ def density(G: Graph[_Node]): ...
 def degree_histogram(G: Graph[_Node]) -> list[int]: ...
 
 @overload
-def is_directed(G: PlanarEmbedding[Hashable]) -> Literal[False]: ...  # type: ignore[misc] # Incompatible return types
+def is_directed(G: PlanarEmbedding[_Node]) -> Literal[False]: ...  # type: ignore[misc] # Incompatible return types
 @overload
-def is_directed(G: DiGraph[Hashable]) -> Literal[True]: ...  # type: ignore[misc] # Incompatible return types
+def is_directed(G: DiGraph[_Node]) -> Literal[True]: ...  # type: ignore[misc] # Incompatible return types
 @overload
-def is_directed(G: Graph[Hashable]) -> Literal[False]: ...
+def is_directed(G: Graph[_Node]) -> Literal[False]: ...
 
 def freeze(G: Graph[_Node]): ...
 def is_frozen(G: Graph[Incomplete]) -> bool: ...
@@ -85,7 +85,7 @@ def create_empty_copy(G: Graph[_Node], with_data: bool = True): ...
 # incomplete: Can "Any scalar value" be enforced?
 @overload
 def set_node_attributes(
-    G: Graph[Hashable],
+    G: Graph[_Node],
     values: SupportsItems[_Node, Unused],
     name: str,
     *,
@@ -126,9 +126,7 @@ def set_edge_attributes(
     **backend_kwargs,
 ) -> None: ...
 @overload
-def set_edge_attributes(
-    G: Graph[Hashable], values, name: None = None, *, backend: str | None = None, **backend_kwargs
-) -> None: ...
+def set_edge_attributes(G: Graph[_Node], values, name: None = None, *, backend: str | None = None, **backend_kwargs) -> None: ...
 
 @_dispatchable
 def get_edge_attributes(G: Graph[_Node], name: str, default=None) -> dict[tuple[_Node, _Node], Incomplete]: ...
@@ -143,7 +141,7 @@ def is_weighted(G: Graph[_Node], edge: tuple[_Node, _Node] | None = None, weight
 @_dispatchable
 def is_negatively_weighted(G: Graph[_Node], edge: tuple[_Node, _Node] | None = None, weight: str = "weight") -> bool: ...
 @_dispatchable
-def is_empty(G: Graph[Hashable]) -> bool: ...
+def is_empty(G: Graph[_Node]) -> bool: ...
 def nodes_with_selfloops(G: Graph[_Node]) -> Generator[_Node]: ...
 
 @overload
@@ -176,7 +174,7 @@ def selfloop_edges(
 ) -> Generator[tuple[_Node, _Node, int, _U]]: ...
 
 @_dispatchable
-def number_of_selfloops(G: Graph[Hashable]) -> int: ...
+def number_of_selfloops(G: Graph[_Node]) -> int: ...
 def is_path(G: Graph[_Node], path: Iterable[Incomplete]) -> bool: ...
 def path_weight(G: Graph[_Node], path: Collection[Incomplete], weight: str) -> int: ...
 def describe(G: Graph[_Node], describe_hook: Callable[[Graph[_Node]], dict[str, Incomplete]] | None = None) -> None: ...