In each of the following parts, either say "this results in an error"; or write down the output from running the code (error free). (a) def f(x): y += 1 z = 2 return x x = 1 y = -1 z= f(y) print(x, y, z) print(x is z) (b) x = [] def f(p = x): print (p) p.append(1) f() x += [2] f() x = [3] f([4]) f()