Rename .py to .pyi.

3/_heapq.pyi

@@ -0,0 +1,27 @@
+"""Stub file for the '_heapq' module."""
+# This is an autogenerated file. It serves as a starting point
+# for a more precise manual annotation of this module.
+# Feel free to edit the source below, but remove this header when you do.
+
+from typing import List, Tuple, Dict, Undefined, GenericType
+
+def heapify(*args, **kwargs) -> None:
+    raise TypeError()
+
+def heappop(*args, **kwargs) -> object:
+    raise IndexError()
+    raise TypeError()
+
+def heappush(*args, **kwargs) -> None:
+    raise TypeError()
+
+def heappushpop(*args, **kwargs) -> object:
+    raise TypeError()
+
+def heapreplace(*args, **kwargs) -> object:
+    raise IndexError()
+    raise TypeError()
+
+def nlargest(a: int, b) -> List[object]: ...
+
+def nsmallest(a: int, b) -> List[object]: ...