fix str.maketrans 2 and 3 arguments cases

tests/snippets/strings.py

@@ -162,7 +162,7 @@ assert "abc".translate({97: '🎅', 98: None, 99: "xd"}) == "🎅xd"
 
 # str.maketrans
 assert str.maketrans({"a": "abc", "b": None, "c": 33}) == {97: "abc", 98: None, 99: 33}
-assert str.maketrans("hello", "world", "rust") == {103: "w", 101: "o", 108: "l", 111: "d", "r": None, "u": None, "s": None, "t": None}
+assert str.maketrans("hello", "world", "rust") == {104: 119, 101: 111, 108: 108, 111: 100, 114: None, 117: None, 115: None, 116: None}
 
 def try_mutate_str():
    word = "word"

vm/src/obj/objstr.rs

@@ -884,7 +884,7 @@ impl PyString {
             let new_dict = vm.context().new_dict();
             if to_str.len(vm) == from_str.len(vm) {
                 for (c1, c2) in from_str.value.chars().zip(to_str.value.chars()) {
-                    new_dict.set_item(c1.to_string(), vm.new_str(c2.to_string()), vm)?;
+                    new_dict.set_item(c1 as u32, vm.new_int(c2 as u32), vm)?;
                 }
             } else {
                 return Err(vm.new_value_error(
@@ -893,7 +893,7 @@ impl PyString {
             }
             if let OptionalArg::Present(none_str) = none_str {
                 for c in none_str.value.chars() {
-                    new_dict.set_item(c.to_string(), vm.get_none(), vm)?;
+                    new_dict.set_item(c as u32, vm.get_none(), vm)?;
                 }
             }
             new_dict.into_pyobject(vm)

whats_left.sh

@@ -8,4 +8,4 @@ python3 not_impl_gen.py
 
 cd ..
 
-cargo +nightly run -- tests/snippets/whats_left_to_implement.py
+cargo run -- tests/snippets/whats_left_to_implement.py