def fun1(a,b):
    return

def fun2(a):
    fun1(a,b=None) # gives no error

#############

def fun3(a,b):
    return

def fun4(**kwargs):
    fun3(**kwargs,b=None) # gives no error

#############

def fun5(a,b):
    return

def fun6():
    fun5(*[""], b=None) # gives Error [bad-keyword-argument]: Multiple values for argument `b` in function `fun5`

fun6() # no crash, as expected