Why we use {o} in python. I'm beginner

Answer 1

Mirielle is right, it's used in string as named placeholder for format function.
PRO TIP: don't call your variables 'o', please don't. Names should be self-descriptive

full_name = "{first_name} {last_name}".format(first_name="Tom", last_name="Tomasson")
print(full_name)
#output: Tom Tomasson

Answer 2

Tq