scdict.py

class scdict(dict):
    """
    Separate chaining dictionary implementation allows
    for multiple values to be assigned to a single key
    in a list.
    """
    def __setitem__(self, key, val):
        """
        Sets a value to a key, and if the key already exists, 
        make a list of all of the values assigned
        """
        newval = val
        if key in self:
            oldval = self.__getitem__(key)
            if type(oldval) == type([]):
                newval = oldval + [newval] 
            else:
                newval = [oldval, val]
        dict.__setitem__(self, key, newval)

def testit():
    """ Just show it works """
    td = scdict()
    td['first'] = 'this'
    td['first'] = 'might'
    td['first'] = 'work'
    print(td)