Method reserve

crates/vm/src/stdlib/marshal.rs:147–152

(&mut self, obj: &PyObjectRef)

            }
        }
        fn reserve(&mut self, obj: &PyObjectRef) -> u32 {
            let idx = self.next_idx;
            self.map.insert(obj.get_id(), idx);
            self.next_idx += 1;
            idx
        }
    }

    fn write_object(