Fix py3k warnings in 1/0 in tests. (#4072)

diff --git a/Lib/ctypes/test/test_parameters.py b/Lib/ctypes/test/test_parameters.py
index c6231f7..23c1b6e 100644
--- a/Lib/ctypes/test/test_parameters.py
+++ b/Lib/ctypes/test/test_parameters.py
@@ -202,7 +202,7 @@
         class WorseStruct(Structure):
             @property
             def __dict__(self):
-                1/0
+                1/0.0
         with self.assertRaises(ZeroDivisionError):
             WorseStruct().__setstate__({}, b'foo')
 
diff --git a/Lib/json/tests/test_speedups.py b/Lib/json/tests/test_speedups.py
index 6ff8401..a6b7c38 100644
--- a/Lib/json/tests/test_speedups.py
+++ b/Lib/json/tests/test_speedups.py
@@ -3,7 +3,7 @@
 
 class BadBool:
     def __nonzero__(self):
-        1/0
+        1/0.0
 
 
 class TestSpeedups(CTest):
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index d2a4f21..8a6d172 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -313,10 +313,10 @@
         # long/int subclass argument.
         class BadInt(int):
             def __abs__(self):
-                1/0
+                1/0.0
         class BadLong(long):
             def __abs__(self):
-                1/0
+                1/0.0
         self.gen.seed(42)
         expected_value = self.gen.random()
         for seed_arg in [42L, BadInt(42), BadLong(42)]: