write the python code that automatically plays the Blocks World game with 3 blocks : 1, 2, 3

user can enter a start set which represents the initial position of these 3 blocks, for example if user enters [123], it means block 1 is on the top, block 2 is on the middle and block 3 is on the bottom.

and then user can enter another set which represents the goal position for the blocks, if user enters [3,21] which means block 1 stands alone and block 2 is on the top of block 3.

Write the code that will presents each move of the play, for the above example it would show:

[1,23]

[1,2,3]

[3,21]

Total of 2 moves