Python字典没有返回所有它的项目

Question

I'm having an issue with my code were I read a text file, put the information in the file inside a list, and then convert the list into a dictionary.

The problem is that when I try to print the items contained in it (be it the entire dictionary or the keys or values only), it only prints one key/value pair.

In fact, the dictionary only contains that particular key/value pair and nothing more.

Here is my code:

class Babies:
    b_list = []
    b_dict = {}

    def __init__(self, scotbabies=None):  # placeholder
        self.scotbabies = scotbabies

    def read_names_from_file(self, file):
        global b_list
        global b_dict

        for line in open(file):
            b_list = line.split()
            b_dict = {k: v for k, v in (b_list for word in b_list)}
            print b_dict # if I print the dictionary at this point it will

            # print the entire dictionary. If I try to print it inside another
            # function or elsewhere, it will only print the first key/value pair.


babies = Babies()
babies.read_names_from_file('scotbabies2014.txt')

The text file contains a list of all the names of the babies born in Scotland along with their gender.

Answer 1

You are redefining the entire dictionary every iteration of the loop.

b_dict = {k: v for k, v in (b_list for word in b_list)} reassigns b_dict to a new dictionary.

You should look into the dictionary type's update function, which kind of merges two dictionaries.