Merge pull request #3609 from Mr-Neutr0n/fix/wildcard-backward-compat

add backward compat alias for _Wildcard

Author: T4rk1n

dash/dependencies.py

@@ -31,6 +31,11 @@ def to_json(self) -> str:
 ALL = Wildcard.ALL
 ALLSMALLER = Wildcard.ALLSMALLER
 
+# Backward compatibility alias — the class was renamed from _Wildcard to
+# Wildcard in Dash 3.4.  Third-party packages (e.g. dash-pydantic-form)
+# still import the old private name.
+_Wildcard = Wildcard
+
 
 class DashDependency:  # pylint: disable=too-few-public-methods
     component_id: ComponentIdType