bpo-32473: Improve ABCMeta._dump_registry() readability (pythonGH-5091)

(cherry picked from commit ae12f5d)

Author: yahya-abou-imran

Lib/abc.py

@@ -170,9 +170,11 @@ def _dump_registry(cls, file=None):
         """Debug helper to print the ABC registry."""
         print("Class: %s.%s" % (cls.__module__, cls.__qualname__), file=file)
         print("Inv.counter: %s" % ABCMeta._abc_invalidation_counter, file=file)
-        for name in sorted(cls.__dict__.keys()):
+        for name in cls.__dict__:
             if name.startswith("_abc_"):
                 value = getattr(cls, name)
+                if isinstance(value, WeakSet):
+                    value = set(value)
                 print("%s: %r" % (name, value), file=file)
 
     def __instancecheck__(cls, instance):

Misc/NEWS.d/next/Library/2018-01-10-20-37-59.bpo-32473.mP_yJG.rst

@@ -0,0 +1 @@
+Improve ABCMeta._dump_registry() output readability