diff --git a/py/builtin.h b/py/builtin.h
index 743f748da0dba54381053047f3d2c3d260aeeb6f..337524899a6ea4a52586d076d93d4e1ad1bb4e18 100644
--- a/py/builtin.h
+++ b/py/builtin.h
@@ -37,6 +37,7 @@ MP_DECLARE_CONST_FUN_OBJ(mp_namedtuple_obj);
 
 MP_DECLARE_CONST_FUN_OBJ(mp_op_contains_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_op_getitem_obj);
+MP_DECLARE_CONST_FUN_OBJ(mp_op_setitem_obj);
 
 extern const mp_obj_module_t mp_module___main__;
 extern const mp_obj_module_t mp_module_array;
diff --git a/py/objdict.c b/py/objdict.c
index 2c56540d152724bd114a5c248ce87a50314eb1e7..1bebf086478620bf0eb9dccd08a5ae729c26febd 100644
--- a/py/objdict.c
+++ b/py/objdict.c
@@ -497,6 +497,7 @@ STATIC const mp_map_elem_t dict_locals_dict_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_update), (mp_obj_t)&dict_update_obj },
     { MP_OBJ_NEW_QSTR(MP_QSTR_values), (mp_obj_t)&dict_values_obj },
     { MP_OBJ_NEW_QSTR(MP_QSTR___getitem__), (mp_obj_t)&mp_op_getitem_obj },
+    { MP_OBJ_NEW_QSTR(MP_QSTR___setitem__), (mp_obj_t)&mp_op_setitem_obj },
 };
 
 STATIC MP_DEFINE_CONST_DICT(dict_locals_dict, dict_locals_dict_table);
diff --git a/py/opmethods.c b/py/opmethods.c
index af2524cf2062f72f01b114ffe41db11a0ff06a1c..f0f19b6dfbc6c2ff8120f03d80c67d714e2bc81f 100644
--- a/py/opmethods.c
+++ b/py/opmethods.c
@@ -13,6 +13,12 @@ STATIC mp_obj_t op_getitem(mp_obj_t lhs_in, mp_obj_t rhs_in) {
 }
 MP_DEFINE_CONST_FUN_OBJ_2(mp_op_getitem_obj, op_getitem);
 
+STATIC mp_obj_t op_setitem(mp_obj_t self_in, mp_obj_t key_in, mp_obj_t value_in) {
+    mp_store_subscr(self_in, key_in, value_in);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_3(mp_op_setitem_obj, op_setitem);
+
 STATIC mp_obj_t op_contains(mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_type_t *type = mp_obj_get_type(lhs_in);
     return type->binary_op(MP_BINARY_OP_IN, lhs_in, rhs_in);