自定义函数
例一:

def hello():
    print("K")
    print("J")
    print("I")
    print('\n')

hello()
hello()
hello()

例二:

def hello(name):
    print('hello '+name)

hello("Alice")

例三:

def io(i):
    if i <10:
        print("小于")
    elif i == 10:
        print('等于')
    else:
        print('大于')
io(10)