Need help getting the output

[perfringo]

As always there are different ways to achieve desired result. Following snippet is using built in string method str.zfill() combined with for loop and slicing:

>>> user_input = '5'                                               
>>> num = ''.join(str(x) for x in range(1, int(user_input) + 1))  # results '12345'
>>> for x in reversed(num):                                       # in reverse order 5->4->3->2->1
...     print(num[:int(x)].zfill(len(num)))                       # slice padded with zeros 
...
12345
01234
00123
00012
00001