BUG: Handle OverflowError by comparing False

instead of raising

tests/test_assets.py

@@ -232,6 +232,8 @@ class AssetTestCase(TestCase):
         self.assertNotEqual(s_23, 23.5)
         self.assertNotEqual(s_23, [])
         self.assertNotEqual(s_23, None)
+        # Compare to a value that doesn't fit into a platform int:
+        self.assertNotEqual(s_23, sys.maxsize + 1)
 
         self.assertLess(s_23, s_24)
         self.assertLess(s_23, 24)

zipline/assets/_assets.pyx

@@ -92,12 +92,12 @@ cdef class Asset:
 
         try:
             x_as_int = PyNumber_Index(x)
-        except TypeError:
+        except (TypeError, OverflowError):
             return NotImplemented
 
         try:
             y_as_int = PyNumber_Index(y)
-        except TypeError:
+        except (TypeError, OverflowError):
             return NotImplemented
 
         compared = x_as_int - y_as_int