std::chrono::operator ==,!= (std::chrono::year_month_weekday)
From cppreference.com
                    
                                        
                    < cpp | chrono | year month weekday
                    
                                                            
                    | constexpr bool operator==(const std::chrono::year_month_weekday& x,  const std::chrono::year_month_weekday& y) noexcept; | (since C++20) | |
| constexpr bool operator!=(const std::chrono::year_month_weekday& x,  const std::chrono::year_month_weekday& y) noexcept; | (since C++20) | |
Compares the two year_month_weekday objects x and y.
Return value
1) x.year() == y.year() && x.month() == y.month() && x.weekday_indexed() == y.weekday_indexed()
2) !(x == y)