How to split a number string using a comma in every 3rd digit from the right

Question

A beginner here! Can I ask how to split a number string in every 3rd digit from the right and put a comma in between and do it again.

>>>num = '12550'

how can I make that into this

>>>12,550

Answer 1

You can use this neat trick:

num = 123456789
print ("{:,.2f}".format(num))

which outputs:

123,456,789.00

If you don't want the decimal places just use:

print ("{:,}".format(num))