Task: Program Execution
Input (English): M, 4, D, 9, a, Z
Output (English): [['M', '4', 'D', '9', 'a'], ['M', '4', 'D', '9', 'Z'], ['M', '4', 'D', 'a', 'Z'], ['M', '4', '9', 'a', 'Z'], ['M', 'D', '9', 'a', 'Z'], ['4', 'D', '9', 'a', 'Z']]