Write a function called golden ratio. m that returns the number of iteration required to find the golden ratio. The golden ratio can be approximated by the Fibonacci sequence by taking the ratio of the n th and the (n − 1)th term. You will find out that the ratio is getting closer and closer to 1.61803398875... The Fibonacci sequence and golden ratio is defined as below. The function should return the smallest n such that golden ratio converges (i. e. change between last value and current value is less than 10−9 ).