I don't understand Arguments

Question

To be exact, I don't understand how this code outputs number 8!

>>>
def function(variable):
variable += 1
print(variable)
>>>

Answer 1

It is a function definition. It adds 1 to its argument and prints the augmented value.

The above will print 8 only if you call the function with 7 as argument.

Answer 2

Here you are:
https://code.sololearn.com/cA8bCguyd3jL/?ref=app

Answer 3

Could you write an example code? The one in my course is confusing to me.