I changed the code and distorted it to understand the interference of the parameters. Look at the code. I do not understand.

Question

https://code.sololearn.com/c4k84t8eq3oT/?ref=app

Answer 1

What do you not understand about it?

Answer 2

Your function prints the 3rd argument called foo.
function(00000,"4", 1,) ##prints 1
function("e","80ghuytreghj", "eg")##prints "eg"

The default value "spa" will be printed if you do not provide it.
e.g.:
function(00000,"4") ##prints "spa"