Remove md_none

Author: jaraco

Lib/importlib/metadata/__init__.py

@@ -1115,7 +1115,7 @@ def packages_distributions() -> Mapping[str, list[str]]:
     pkg_to_dist = collections.defaultdict(list)
     for dist in distributions():
         for pkg in _top_level_declared(dist) or _top_level_inferred(dist):
-            pkg_to_dist[pkg].append(md_none(dist.metadata)['Name'])
+            pkg_to_dist[pkg].append(dist.metadata['Name'])
     return dict(pkg_to_dist)