从一串文本中获取三元组

Question

定义传递一串文本的get_triples_dict()函数 作为参数。该函数首先将参数字符串转换为 小写，然后返回一个包含所有键的字典 独特的连续三个字母字符来自文本，以及 对应的值是连续三次的次数 字母字符出现在文本中。使用isalpha()方法 检查一个字符是否是字母。字典应该只 包含多次出现的条目。你的字典后 已创建并填充，您需要删除任何键值对 具有相应的值1。

有人可以帮我修改我的代码，以便我能获得正确的输出吗？我试过了，但它并没有完全奏效。我只需要get_triples_dict函数的帮助，我不需要触及test_get_triples_dict函数。以下是我到目前为止的预期输出：

def get_triples_dict(text):

       triples_dict = {}

       word = ""

       mod_text = ""

       # convert the text to contain only letters and convert all letters to lowercase

       for i in range(0,len(text)):

                      if text[i].isalpha():

                                     mod_text = mod_text + text[i].lower()

       # if length of text >= 3 letters                     

       if(len(mod_text) >= 3):

                      # loop over the text

                      for i in range(0,len(mod_text)-2):

                                     word = mod_text[i:i+3] # extract 3 letter word from starting with the letter at i

                                     if word in triples_dict.keys(): # if word is in dictionary then increment its frequency

                                                    triples_dict[word] = triples_dict[word] + 1

                                     else: # else insert the word in dictionary with frequency 1

                                                    triples_dict[word] = 1



       keys = triples_dict.keys() # get the list of keys in the dictionary

       # loop over the keys list

       for i in range(0,len(keys)):

                      if triples_dict[keys] == 1: #if frequency of the word is 1, then remove the entry from dictionary

                                     del triples_dict[keys]
                                     i = i - 1 # decrement i

       return triples_dict # return the dictionary


def test_get_triples_dict():
    print("1.")
    print_dict_in_key_order(get_triples_dict('super, duper'))
    print("\n2.")
    print_dict_in_key_order(get_triples_dict("ABC ABC ABC"))
    print("\n3.")
    print_dict_in_key_order(get_triples_dict("Sometimes the smallest things make more room in your heart"))
    print("\n4.")
    print_dict_in_key_order(get_triples_dict("My favourite painting is the painting i did of my dog in that painting in my den"))

预期输出：