Using default a empty dictionary as a default value

[C Gillespie]

Dear All,
I ran my code through pylint to clean it up and one of the (many) errors it
through up was
Dangerous default value {} as argument
Bascially, I have:

class NewClass:
    def __init__(self,  myDict={}):
        for key, value in myDict:
            print key, value

Obviously, this is not the way it should be done. Should I have a default
value of None for myDict and test for it? Or is there some other way?

Thanks

Colin