What is a clean "pythonic" way to implement multiple constructors?

I can't find a definitive answer for this. As far as I know, you can't have multiple __init__ functions in a Python class. So how do I solve this problem?

Suppose I have a class called Cheese with the number_of_holes property. How can I have two ways of creating cheese objects...

• One that takes a number of holes like this: parmesan = Cheese(num_holes=15).

• And one that takes no arguments and just randomizes the number_of_holes property: gouda = Cheese().

I can think of only one way to do this, but this seems clunky:

class Cheese:
    def __init__(self, num_holes=0):
        if num_holes == 0:
            # Randomize number_of_holes
        else:
            number_of_holes = num_holes

What do you say? Is there another way?

Actually None is much better for "magic" values:

class Cheese:
    def __init__(self, num_holes=None):
        if num_holes is None:
            ...

Now if you want complete freedom of adding more parameters:

class Cheese:
    def __init__(self, *args, **kwargs):
        # args -- tuple of anonymous arguments
        # kwargs -- dictionary of named arguments
        self.num_holes = kwargs.get('num_holes', random_holes())

To better explain the concept of *args and **kwargs (you can actually change these names):

def f(*args, **kwargs):
   print('args:', args, 'kwargs:', kwargs)

>>> f('a')
args: ('a',) kwargs: {}
>>> f(ar='a')
args: () kwargs: {'ar': 'a'}
>>> f(1,2,param=3)
args: (1, 2) kwargs: {'param': 3}

http://docs.python.org/reference/expressions.html#calls

Stack Overflow Q#682504, score: 976