# positional-only parameters
# available in python 3.8+

def s(a,b,/): # notice the /
    print(a+b)

s(10,20) # OK
# s(a=10,b=20) # error

def s2(a,b,/,c):
    # c can be named
    print(a+b+c)

s2(10,20,c=30)

# Output:
# 30
# 60
