abcd

x = [[1,2,3,4,5],[21,22,23,24,25],[31,32,33,34,35]]
y = [0] * 3

def first():
	print(x[1])

def second():
	print(x[0][2])

def third():
	print(x[2][1 : 3])

def fourth():
	print(x[0][0:len(x[0]):2])

def fifth():
	for i in range(len(x)):
		y[i] = sum(x[i]) / len(x[i])
	print(y)

first()
second()
third()
fourth()
fifth()