Task: Program Execution
Input (English): M, 4, 7, 4, 3, 7, b
Output (English): [['M', '4', '7', '4', '3', '7'], ['M', '4', '7', '4', '3', 'b'], ['M', '4', '7', '4', '7', 'b'], ['M', '4', '7', '3', '7', 'b'], ['M', '4', '4', '3', '7', 'b'], ['M', '7', '4', '3', '7', 'b'], ['4', '7', '4', '3', '7', 'b']]