diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py
index 8f5b8f0e171..cac2105b6aa 100644
--- a/Lib/test/test_builtin.py
+++ b/Lib/test/test_builtin.py
@@ -658,8 +658,6 @@ def badfunc():
         self.assertEqual(list(filter(lambda x: x>=3, (1, 2, 3, 4))), [3, 4])
         self.assertRaises(TypeError, list, filter(42, (1, 2)))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_filter_pickle(self):
         for proto in range(pickle.HIGHEST_PROTOCOL + 1):
             f1 = filter(filter_char, "abcdeabcde")
diff --git a/Lib/test/test_itertools.py b/Lib/test/test_itertools.py
index 652ffdde10a..7fa961f8557 100644
--- a/Lib/test/test_itertools.py
+++ b/Lib/test/test_itertools.py
@@ -856,8 +856,6 @@ def keyfunc(obj):
         keyfunc.skip = 1
         self.assertRaises(ExpectedError, gulp, [None, None], keyfunc)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_filter(self):
         self.assertEqual(list(filter(isEven, range(6))), [0,2,4])
         self.assertEqual(list(filter(None, [0,1,0,2,0])), [1,2])
diff --git a/extra_tests/snippets/builtin_complex.py b/extra_tests/snippets/builtin_complex.py
index 61dc7071240..ecba467e8dc 100644
--- a/extra_tests/snippets/builtin_complex.py
+++ b/extra_tests/snippets/builtin_complex.py
@@ -41,6 +41,7 @@
 # "can't mod complex numbers.
 assert_raises(TypeError, lambda: complex(2, -3) % 2)
 assert_raises(TypeError, lambda: 2 % complex(2, -3))
+assert_raises(TypeError, lambda: complex(2, -3).__mod__(2))
 
 # __floordiv__, __rfloordiv__
 # can't take floor of complex number.
diff --git a/vm/src/builtins/complex.rs b/vm/src/builtins/complex.rs
index f33d4856f76..a8aab079300 100644
--- a/vm/src/builtins/complex.rs
+++ b/vm/src/builtins/complex.rs
@@ -204,6 +204,11 @@ impl PyComplex {
 
 #[pyimpl(flags(BASETYPE), with(Comparable, Hashable, Constructor))]
 impl PyComplex {
+    #[pymethod(name = "__mod__")]
+    fn mod_(&self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        return Err(vm.new_type_error("can't mod complex numbers.".to_owned(),))
+    }
+
     #[pymethod(magic)]
     fn complex(zelf: PyRef<Self>, vm: &VirtualMachine) -> PyRef<PyComplex> {
         if zelf.is(&vm.ctx.types.complex_type) {
diff --git a/vm/src/builtins/filter.rs b/vm/src/builtins/filter.rs
index 1455aec8c03..39bf70e57e4 100644
--- a/vm/src/builtins/filter.rs
+++ b/vm/src/builtins/filter.rs
@@ -37,7 +37,15 @@ impl Constructor for PyFilter {
 }
 
 #[pyimpl(with(IterNext, Constructor), flags(BASETYPE))]
-impl PyFilter {}
+impl PyFilter {
+    #[pymethod(magic)]
+    fn reduce(&self, vm: &VirtualMachine) -> (PyTypeRef, (PyObjectRef, PyIter)) {
+        (
+            vm.ctx.types.filter_type.clone(),
+            (self.predicate.clone(), self.iterator.clone()),
+        )
+    }
+}
 
 impl IterNextIterable for PyFilter {}
 impl IterNext for PyFilter {