Python: user definied number format in string

Question

May be a question that has already been asked: How can I print an integer in a user definied format.

For example

input = 123456
print(".....".format(input))

where the output should be:

"ab123.45.6"

Unfortunately, slicing in string formating is not possible. So something like:

"ab{0[:2]}.{0[3:4]}.{0[5]}".format(str(input))

would not work. But is there a better solution than:

"ab{0[0]}{0[1]}{0[2]}.{0[3]}{0[4]}.{0[5]}".format(str(input))

Answer 1

Why not make the slices format() arguments? It looks a bit cleaner.

user_input = str(123456)
print("ab{0}.{1}.{2}".format(user_input[:3], user_input[3:5], user_input[5]))