ITP2 - OOP Tutorials - Calling Methods With self

To disambiguate from creating a local variable, we need to use
self.name= to let Ruby know that we're calling a method. So our
change_info code should be updated to this:

def change_info(n, h, w)
  self.name = n
  self.height = h
  self.weight = w
end

This tells Ruby that we're calling a setter method, not creating a local
variable. To be consistent, we could also adopt this syntax for the
getter methods as well, though it is not required.

def info
  "#{self.name} weighs #{self.weight} and is #{self.height} tall."
end

Finally, if we run our code with the updated change_info method that
uses the self. syntax, our code works beautifully