def update_args(self, args):
        """Update from command line args. """
        for cfg in args:
            keys, v = cfg.split('=', maxsplit=1)
            keylist = keys.split('.')

            dic = self
            for i, k in enumerate(keylist[:-1]):
                assert k in dir(dic), "Unknown config key: {}".format(keys)
                dic = getattr(dic, k)
            key = keylist[-1]

            oldv = getattr(dic, key)
            if not isinstance(oldv, str):
                v = eval(v)
            setattr(dic, key, v)
Update from command line args.