import pickle


def loads_functions(serializers):
    """Return a pair of loads functions (for the key and value).

    Parameters:
        serializers: A Serializers instance (such as a namedtuple) for
            serializing from Python objects to bytes.  If a serializer is
            None, use pickle.  Otherwise, use its `dumps` function.
    """
    if serializers is None:
        key_s = None
        value_s = None
    else:
        key_s = serializers.key_s
        value_s = serializers.value_s

    if key_s is None:
        loads_key = pickle.loads
    else:
        loads_key = key_s.loads

    if value_s is None:
        loads_value = pickle.loads
    else:
        loads_value = value_s.loads

    return loads_key, loads_value