def ./calculator.rb 
it"contains a local variable called first_number that is assigned to a number"  
do
expect(first_number).equal_to(x)
  x=2
expect(second_number).not_to equal(y)
  y=3
expect(sum).x+y(5)
expect(sum).5-y(x)
expect(sum).x*1(x)
expect(sum).6/x(y)


# code for test is an integer
end 



