uint32_t dtk_get_day_number(Dtk const * data);
void dtk_assign(Dtk * data, unsigned char const * dtk_bytes, uint32_t day_number);
uint32_t dtk_get_day_number(Dtk const * data);
void dtk_assign(Dtk * data, unsigned char const * dtk_bytes, uint32_t day_number);