RustPython/extra_tests/benchmarks/perf_fib.py

def fib(n):
    a = 1
    b = 1
    for _ in range(n - 1):
      temp = b
      b = a + b
      a = temp

    return b

print(fib(1))
print(fib(2))
print(fib(3))
print(fib(4))
print(fib(5))