Is there are good DRY fix for this painful design pattern?

[Antoon Pardon]

On 26-02-18 15:41, Steven D'Aprano wrote:
> I have a class with a large number of parameters (about ten) assigned in 
> `__init__`. The class then has a number of methods which accept 
> *optional* arguments with the same names as the constructor/initialiser 
> parameters. If those arguments are None, the defaults are taken from the 
> instance attributes.
>
This is what I came up with at short notice:

def passthrough(func):
    def wrapper(self, **kwds):
        for argn in "bashful doc dopey grumpy happy sleepy sneezy".split():
            if argn not in kwds:
                kwds[argn] = getattr(self, argn)
        func(self, **kwds)
    return wrapper
            

class Foo:
    def __init__(self, bashful, doc, dopey, grumpy, 
                       happy, sleepy, sneezy):
        self.bashful = bashful
        self.doc = doc
        self.dopey = dopey
        self.grumpy = grumpy
        self.happy = happy
        self.sleepy = sleepy
        self.sneezy = sneezy

    @passthrough
    def spam(self, bashful=None, doc=None, dopey=None, 
                   grumpy=None, happy=None, sleepy=None,
                   sneezy=None):
        print(bashful, doc, dopey, grumpy, happy, sleepy, sneezy)

foo = Foo('a', 'b', 'c', 'd', 'e', 'f', 'g')
foo.spam(happy = 1) # prints => a b c d 1 f g