Update run-weakref.test

Author: BobTheBuidler

mypyc/test-data/run-weakref.test

@@ -10,15 +10,15 @@ def test_weakref_ref():
     obj = asyncio.new_event_loop()
     r = ref(obj)
     assert r() is obj
-    del obj
+    obj = None
     assert r() is None, r()
 
 def test_weakref_ref_with_callback():
     # some random weakreffable object
     obj = asyncio.new_event_loop()
     r = ref(obj, lambda x: x)
     assert r() is obj
-    del obj
+    obj = None
     assert r() is None, r()
 
 [case testWeakrefProxy]
@@ -31,7 +31,7 @@ def test_weakref_proxy():
     obj = asyncio.new_event_loop()
     p = proxy(obj)
     assert p.is_closed() is False
-    del obj
+    obj = None
     with pytest.raises(ReferenceError):
         p.is_closed()
 
@@ -40,6 +40,6 @@ def test_weakref_proxy_with_callback():
     obj = asyncio.new_event_loop()
     p = proxy(obj, lambda x: x)
     assert p.is_closed() is False
-    del obj
+    obj = None
     with pytest.raises(ReferenceError):
         p.is_closed()