Make sure to avoid duplicates in completions

jedi/api/strings.py

@@ -55,12 +55,12 @@ def _completions_for_dicts(inference_state, dicts, literal_string, cut_end_quote
         dict_key_str = _create_repr_string(literal_string, dict_key)
         if dict_key_str.startswith(literal_string):
             n = dict_key_str[len(literal_string):-len(cut_end_quote) or None]
-            name = StringName(inference_state, n)
+            name = StringName(inference_state, dict_key_str[:-len(cut_end_quote) or None])
             yield Completion(
                 inference_state,
                 name,
                 stack=None,
-                like_name_length=0,
+                like_name_length=len(literal_string),
                 is_fuzzy=fuzzy
             )