Flatten Iterator for Vector of Iterators with getnext() and hasnext() Methods

coinbase Implement an iterator that takes a vector<iterator> as input. Implement the following methods: getnext(): Returns the next element. hasnext(): Checks if there are more elements available for iteration. The provided iterators may be empty. Test Case: vec_of_iters = [[1, 2, 3], [4, 5], [6, 7, 8, 9]] output = [] while iterator.hasnext(): output.append(iterator.getnext()) assert output == [1, 2, 3, 4, 5, 6, 7, 8, 9] Example Input {'vec_of_iters': [[1, 2, 3], [4, 5], [6, 7, 8, 9]]}