Encode a list/tuple.

def _encode_list(name, value, check_keys, opts):
    """Encode a list/tuple."""
    lname = gen_list_name()
    data = b"".join([_name_value_to_bson(next(lname), item,
                                         check_keys, opts)
                     for item in value])
    return b"\x04" + name + _PACK_INT(len(data) + 5) + data + b"\x00"