Refs #29838 -- Fixed make_hashable() for values that have lists or dicts nested in tuples.

And for non-hashable values that are iterable, e.g. sets.

django/utils/hashable.py

@@ -1,9 +1,19 @@
+from django.utils.itercompat import is_iterable
+
+
 def make_hashable(value):
-    if isinstance(value, list):
-        return tuple(map(make_hashable, value))
     if isinstance(value, dict):
         return tuple([
             (key, make_hashable(nested_value))
             for key, nested_value in value.items()
         ])
+    # Try hash to avoid converting a hashable iterable (e.g. string, frozenset)
+    # to a tuple.
+    try:
+        hash(value)
+    except TypeError:
+        if is_iterable(value):
+            return tuple(map(make_hashable, value))
+        # Non-hashable, non-iterable.
+        raise
     return value