Add type_hints for required_graph_inputs�

Author: Dhruvanshu-Joshi

pytensor/graph/basic.py

@@ -908,7 +908,9 @@ def graph_inputs(
 
 
 # def required_graph_inputs(graph:Variable | Iterator[Variable])-> Generator[Variable, None, None]:
-def required_graph_inputs(graph: list[Variable[Any, Any]]) -> list[Variable[Any, Any]]:
+def required_graph_inputs(
+    graph: Variable[Any, Any] | Iterable[Variable[Any, Any]],
+) -> list[Variable[Any, Any]]:
     """
     Get the inputs into PyTensor variables
 
@@ -952,8 +954,8 @@ def required_graph_inputs(graph: list[Variable[Any, Any]]) -> list[Variable[Any,
     """
     from pytensor.compile.sharedvalue import SharedVariable
 
-    # if isinstance(graph, Variable):
-    #     graph = [graph]
+    if isinstance(graph, Variable):
+        graph = [graph]
 
     return [
         v