def fibonacci() -> Iterator[int]:
    """Generate the sequence of Fibonacci.
    https://oeis.org/A000045
    """
    a, b = 1, 2
    while True:
        yield a
        a, b = b, a + b
def fibonacci ( ) -> Iterator [ int ] : a , b = 1 , 2 while True : yield a a , b = b , a + b
Generate the sequence of Fibonacci.
    https://oeis.org/A000045