Add filterfalse.__reduce__

Lib/test/test_itertools.py

@@ -883,8 +883,6 @@ class TestBasicOps(unittest.TestCase):
             c = filter(isEven, range(6))
             self.pickletest(proto, c)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_filterfalse(self):
         self.assertEqual(list(filterfalse(isEven, range(6))), [1,3,5])
         self.assertEqual(list(filterfalse(None, [0,1,0,2,0])), [0,0,0])

vm/src/stdlib/itertools.rs

@@ -875,7 +875,15 @@ mod decl {
     }
 
     #[pyimpl(with(IterNext, Constructor))]
-    impl PyItertoolsFilterFalse {}
+    impl PyItertoolsFilterFalse {
+        #[pymethod(magic)]
+        fn reduce(zelf: PyRef<Self>) -> (PyTypeRef, (PyObjectRef, PyIter)) {
+            (
+                zelf.class().clone(),
+                (zelf.predicate.clone(), zelf.iterable.clone()),
+            )
+        }
+    }
     impl IterNextIterable for PyItertoolsFilterFalse {}
     impl IterNext for PyItertoolsFilterFalse {
         fn next(zelf: &Py<Self>, vm: &VirtualMachine) -> PyResult<PyIterReturn> {