std::chrono::month_weekday::month, std::chrono::month_weekday::weekday_indexed
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                    < cpp | chrono | month weekday
                    
                                                            
                    |   constexpr std::chrono::month month() const noexcept;  | 
(1) | (since C++20) | 
|   constexpr std::chrono::weekday_indexed weekday_indexed() const noexcept;  | 
(2) | (since C++20) | 
Retrieves a copy of the month and weekday_indexed objects stored in *this.
Return value
1) a copy of the std::chrono::month object stored in 
*this2) a copy of the std::chrono::weekday_indexed object stored in 
*this