如何使用python基礎編程語言來解決下面那道完成了壹部分的練習題？

text_list?=?text.split()

dic?=?dict()

for?k?in?range(0,?len(text_list)):

dic[text_list[k]]?=?[]

for?i?in?range(0,?len(text_list)):

if?i?==?0:

dic[text_list[i]]?=?['']

else:

if?text_list[i?-?1]?not?in?dic[text_list[i]]:

dic[text_list[i]]?+=?[text_list[i?-?1]]

return?dic

def?print_dic_in_key_order(dic):

order?=?[i?for?i?in?dic]

order.sort()

for?k?in?order:

print(k,?':',?sorted(dic[k]))

text?=?'a?man?we?saw?saw?a?saw'

previous_words_dict?=?get_previous_words_dict(text)

print_dic_in_key_order(previous_words_dict)

print()

text?=?'my?favourite?painting?is?the?painting?i?did?of?my?dog?in?that?painting?in?my?den'

previous_words_dict?=?get_previous_words_dict(text)

print_dic_in_key_order(previous_words_dict)

print()