type annotate backtrack_depgraph in depgraph.py

lib/_emerge/depgraph.py

@@ -100,6 +100,10 @@
 from _emerge.resolver.circular_dependency import circular_dependency_handler
 from _emerge.resolver.output import Display, format_unmatched_atom
 
+# For Type Annotations
+from typing import List, Tuple, Any
+from _emerge.stdout_spinner import stdout_spinner
+
 # Exposes a depgraph interface to dep_check.
 _dep_check_graph_interface = collections.namedtuple(
     "_dep_check_graph_interface",
@@ -11385,7 +11389,7 @@ def _spinner_stop(spinner):
     portage.writemsg_stdout(f"Dependency resolution took {darkgreen(time_fmt)} s.\n\n")
 
 
-def backtrack_depgraph(settings, trees, myopts, myparams, myaction, myfiles, spinner):
+def backtrack_depgraph(settings: "portage.package.ebuild.config.config", trees: dict, myopts: dict, myparams: dict, myaction: Any, myfiles: List, spinner: "stdout_spinner") -> Tuple[bool, depgraph, List]:
     """
     Raises PackageSetNotFound if myfiles contains a missing package set.
     """