Describe fibonacci!!

Question

Please explain me -
def fibonacci(num):
fibo = [0,1]
i = 2
while i<= num:
next_fibo = fibo[i-1] + fibo[i-2]
fibo.append(next_fibo)
i += 1
return fibo
print(fibonacci(9))

Answer 1

I know the function,also know the fibonacci. But I'm not getting the explnation of the code.