def stringify_list(ls):
    """ string conversion of all elements in a list,
        e.g. stringify_list([1,'2',u'3'])  -> ['1', '2', u'3']

        Mostly a support function for some other things here.
    """    
    if type(ls) is list:
        return list('%s'%s  for s in ls)
    else: # tuple. Or something you shouldn't have handed in without specific expectation.
        return tuple('%s'%s  for s in ls)