Creates a new ExtendedMethod
object.
new_extended_method(name, label, base_method, extended_method)
a short name identifier. Must be alphanumeric.
a longer, human readable label that can have other characters such as spaces, hyphens, etc.
the object of class Method
or
of class Method
that is being extended
a function with arguments "model", "draw", "out", and "base_method".