recursion - Missing 1 required positional argument - Python -

typeerror: sequence() missing 1 required positional argument: 'n', sequence() 

apparently when using sequence(n-1) + sequence(n-2) n not using value function, can fix it?

memo = {0:0,1:1} def sequence(type, n): if type == "fibonacci":     if not n in memo:         memo[n] = sequence(n-1) + sequence(n-2)     else:         return memo[n] 

try this:

sequence(type, n-1) + sequence(type, n-2) 

the error explicit, function sequence expecting 2 parameters, you're passing one. side note, should remove else, , make sure return memo[n] executed @ end - because function must always return value, otherwise recursion won't work.