Workaround for bug in ruamel.yaml. Allow dicts to be indexed by unicode.

Author: Peter Amstutz

typeshed/2.7/__builtin__.pyi

@@ -556,7 +556,10 @@ class dict(MutableMapping[_KT, _VT], Generic[_KT, _VT]):
     @overload
     def fromkeys(seq: Sequence[_T], value: _S) -> Dict[_T, _S]: ...
     def __len__(self) -> int: ...
+    @overload
     def __getitem__(self, k: _KT) -> _VT: ...
+    @overload
+    def __getitem__(self, k: unicode) -> _VT: ...
     def __setitem__(self, k: _KT, v: _VT) -> None: ...
     def __delitem__(self, v: _KT) -> None: ...
     def __contains__(self, o: object) -> bool: ...