heapq: Add simple test.

heapq/test_heapq.py

@@ -0,0 +1,8 @@
+import heapq
+
+
+h = []
+heapq.heappush(h, (10.1, 0))
+heapq.heappush(h, (1.1, 1))
+print(h)
+assert h == [(1.1, 1), (10.1, 0)]