filter_exp_start = name_end + cls._filter_exp_len_struct.size
filter_exp_len, = cls._filter_exp_len_struct.unpack_from(
data[name_end:filter_exp_start])
filter_exp_start = name_end + cls._filter_exp_len_struct.size
filter_exp_len, = cls._filter_exp_len_struct.unpack_from(
data[name_end:filter_exp_start])