python 怎么引入类

from fun import Dog

dog=Dog('husike')

dog.bark()

from fun import Dog,Cat

dog=Dog('husike')

dog.bark()

cat=Cat('maomi')

cat.catch_mouse()

import fun

dog=fun.Dog('husike')

dog.bark()

cat=fun.Cat('maomi')

cat.catch_mouse()

horse=fun.Horse('xiaoma')

horse.run()

from fun import *

dog=Dog('husike')

dog.bark()

cat=Cat('maomi')

cat.catch_mouse()

horse=Horse('xiaoma')

horse.run()