Add AssertionError.

py/emitpass1.c

@@ -45,10 +45,7 @@ static void emit_pass1_load_id(emit_t *emit, qstr qstr) {
     bool added;
     id_info_t *id = scope_find_or_add_id(emit->scope, qstr, &added);
     if (added) {
-        if (qstr == MP_QSTR_AssertionError) {
-            // TODO how much of a hack is this?
-            id->kind = ID_INFO_KIND_GLOBAL_EXPLICIT;
-        } else if (strcmp(qstr_str(qstr), "super") == 0 && emit->scope->kind == SCOPE_FUNCTION) {
+        if (strcmp(qstr_str(qstr), "super") == 0 && emit->scope->kind == SCOPE_FUNCTION) {
             // special case, super is a global, and also counts as use of __class__
             id->kind = ID_INFO_KIND_GLOBAL_EXPLICIT;
             id_info_t *id2 = scope_find_local_in_parent(emit->scope, emit->qstr___class__);

py/runtime.c

@@ -90,6 +90,7 @@ void rt_init(void) {
     mp_map_add_qstr(&map_builtins, MP_QSTR_SyntaxError, mp_obj_new_exception(MP_QSTR_SyntaxError));
     mp_map_add_qstr(&map_builtins, MP_QSTR_ValueError, mp_obj_new_exception(MP_QSTR_ValueError));
     mp_map_add_qstr(&map_builtins, MP_QSTR_OSError, mp_obj_new_exception(MP_QSTR_OSError));
+    mp_map_add_qstr(&map_builtins, MP_QSTR_AssertionError, mp_obj_new_exception(MP_QSTR_AssertionError));
 
     // built-in objects
     mp_map_add_qstr(&map_builtins, MP_QSTR_Ellipsis, mp_const_ellipsis);