You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: 0090-subsets-ii.rs
    path of file: ./repos/NeetCode-Solutions/10_Backtracking/04_Subsets_II
    
    the code of the file until where you have to start completion: /*
Problem: LeetCode 90 - Subsets II

Key Idea:
To find all unique subsets of an array that may contain duplicate el
    
    pub fn subsets_with_dup(nums: Vec<i32>) -> Vec<Vec<i32>> {
        let mut result: Vec<Vec<i32>> = Vec::new();

        let mut current_subset: Vec<i32> = Vec::new();
        let mut sorted_nums = nums.clone();
        sorted_nums.sort();

        Self::backtrack(&mut current_subset, 0, &mut result, &sorted_nums);

        result
    }