Bored to write 4 lines of code when you can write only one ? Yes, me too. I don't like the following code, when my fingers type this kind of code, my brain tell me "That's obvious I want to do that, I shouldn't write it". 
d = {"chicken": 1, "rabbits": 2}
l = ["chicken", "capcat"]
for i in l:
    if not i in d:
        d[i] = 1
    else:
        d[i] += 1
The following class appease a part of my mind. 
class DefaultDict(dict):
    "Dictionary with a default value for key that does not exist"
    def __init__(self, default, iterable_init=[], **kwds):
        super(DefaultDict, self).__init__(iterable_init)
        self.update(kwds)
        self.default = default
    def __getitem__(self, key):
        return self.get(key, self.default)
    def __copy__(self):
        return DefaultDict(self.default, self)
Usage: 
d = DefaultDict(0)
d["capcat"] += 1