Get funcid when create function

I'm developing a extension for pg. Now I have create a event trigger on
ddl_command_end, and this function will be called after I enter create
function statement. In this function I can only get parseTree. In pg source
code, I found a function named "pg_event_trigger_ddl_commands" seems
provide cmds which include funcid. BUT I didn't found any example to call
this function.
who can helps?

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