Task: Program Execution
Input (English): 9, u, 5, 0, 7, 4
Output (English): [['9', 'u', '5', '0', '7'], ['9', 'u', '5', '0', '4'], ['9', 'u', '5', '7', '4'], ['9', 'u', '0', '7', '4'], ['9', '5', '0', '7', '4'], ['u', '5', '0', '7', '4']]