class addition:
	def my_sum1(self,a,b):
		return a+b
	def my_sum2(self,a,b,c):
		return a+b+c
	def my_sum3(self,a,b,c,d):
		return a+b+c+d

a = addition()
print(a.my_sum1(1,2))
print(a.my_sum2(1,2,3))
print(a.my_sum3(1,2,3,4))


	
	

