sigh ofcourse he knows what he means by "by", he wouldn't use a name if he couldn't understand it himself.
The point is that "by" does not tell you anything about what it contains, you need to see the context to deduce what it means.
That means that if you look back on that script in a few weeks time, you'll be completely lost and you'll have to read a sh*tload of code to find out what "by" contains.