STM32L071KZT6 can't select HSE in cubemx

[CZorg.1]

hi i am using STM32L071KZT6 chip in my board and using Cube ide for initialization and code development. in the datasheet it says KZT6 chip has 1 clock input and is configurable as HSE/LSE/HSI/MSI/LSI but in the Cubeide clock config page or System Core/RCC page, i cant select HSE external xtal option.  

[TDK · Accepted solution]

Those pins aren't exposed on the LQFP32 package, so HSE is not available.