斐波拉契数列（Fibonacci）

列表生成式法：

def fib(max):    n, a, b = 0, 0, 1    while n < max:        print(b)        a, b = b, a + b        n = n + 1    return 'done'

生成器：generator法

def fib(max):    n, a, b = 0, 0, 1    while n < max:        yield b        a, b = b, a + b        n = n + 1    return 'done'

列表生成器输出：

g = fib(6)while True:     try:         x = next(g)         print('g:', x)     except StopIteration as e:         print('Generator return value:', e.value)         break