Abount Calendar and impress plugin

i just installed senaite on ubuntu. i have some questions about some functions:
1- is senaite using built in calendar of ubuntu or have a seperate calendar system? i need to use jalali(shamsi or geregorian) calendar and i cant find any option to change it.
2- we are using right to left language here, so i need to turn software into rtl. senaite core have rtl function and when i change my language everything works fine ( some translation needs to improve and i am working on thee right now) but i have a problem with impress plugin, there is no rtl in it. how can i make it rtl?

thnaks in advance

if i am correct, senaite use python calendar. i need to change python calendar to jalali so i can use it in senaite.
am i right?