Confusion regarding _Py_BreakPoint

Question

There is a function,

void
_Py_Breakpoint(void)
{
}

in Objects/object.c. but how does one use it to debug, as its comment says,

for debugging conventions. set a breakpoint here and call it from your dll.

what I did was,

lldb python.exe

b _Py_BreakPoint
call _Py_BreakPoint

but how do I use it?