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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _gen_condition(cls, initial, new_public_keys):
 """Generates ThresholdSha256 conditions from a list of new owners. Note: This method is intended only to be used with a reduce function. For a description on how to use this method, see :meth:`~.Output.generate`. Args: initial (:class:`cryptoconditions.ThresholdSha256`):
 A Condition representing the overall root. new_public_keys (:obj:`list` of :obj:`str`|str):
 A list of new owners or a single new owner. Returns: :class:`cryptoconditions.ThresholdSha256`: """

        try:
            threshold = len(new_public_keys)
        except TypeError:
            threshold = None

        if isinstance(new_public_keys, list) and len(new_public_keys) > 1:
            ffill = ThresholdSha256(threshold=threshold)
            reduce(cls._gen_condition, new_public_keys, ffill)
        elif isinstance(new_public_keys, list) and len(new_public_keys) <= 1:
            raise ValueError('Sublist cannot contain single owner')
        else:
            try:
                new_public_keys = new_public_keys.pop()
            except AttributeError:
                pass
            # NOTE: Instead of submitting base58 encoded addresses, a user
            #       of this class can also submit fully instantiated
            #       Cryptoconditions. In the case of casting
            #       `new_public_keys` to a Ed25519Fulfillment with the
            #       result of a `TypeError`, we're assuming that
            #       `new_public_keys` is a Cryptocondition then.
            if isinstance(new_public_keys, Fulfillment):
                ffill = new_public_keys
            else:
                ffill = Ed25519Sha256(
                    public_key=base58.b58decode(new_public_keys))
        initial.add_subfulfillment(ffill)
        return initial