Question

练习1

#!/usr/bin/env python3
farm_animals = ['cow','pig','horse']
domestic_animals = ['dog','cat','gold fish']
zoo_animals = ['lion','elephant','gorilla']
animals = farm_animals + domestic_animals + zoo_animals
for index_value in range(len(animals)):
    print("{0:d}: {1!s}".format(index_value, animals[index_value]))

练习2

#!/usr/bin/env python3
animals_dictionary = {}
animals_list = ['cow','pig','horse']
other_list = [4567,[4,'turn',7,'left'],'Animals are great.']
for index_value in range(len(animals_list)):
    if animals_list[index_value] not in animals_dictionary:
        animals_dictionary[animals_list[index_value]] = other_list[index_value]
for key, value in animals_dictionary.items():
    print("{0!s}: {1}".format(key, value))

练习3

#!/usr/bin/env python3
list_of_lists = [['cow','pig','horse'], ['dog','cat','gold fish'],\
['lion','elephant','gorilla']]
for animal_list in list_of_lists:
    max_index = len(animal_list)
    output = ''
    for index in range(len(animal_list)):
        if index < (max_index-1):
            output += str(animal_list[index])+','
        else:
            output += str(animal_list[index])+'\n'
print(output)