Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f3/STM32F303/PWR/CSR#0x0
power control/status register
Wakeup flag
Standby flag
PVD output
Enable WKUP1 pin
Enable WKUP2 pin
https://github.com/modm-io/cmsis-svd-stm32