python - 尝试在 Python 中添加到字典时出现 ValueError

Question

所以我有一个这种格式的文件

CountryCode   CountryName
USA           United States

我想做的是做一个字典，代码为键，国名为值。

我有一个函数，它有这样做的意图

def country(string):
    '''reads the contents of a file into a string and closes it.'''

    #open the file
    countryDict = {}
    fin = open(string, 'r')
    for eachline in fin:
        code, country = eachline.split()
        countryDict[code] = country

    print (countryDict)


    return countryDict

但是，当我尝试运行它时，我得到了 ValueError:要解压的值太多(预期为 2)。

此代码不起作用的任何原因？我有一个类似的程序可以使用这样的代码创建用户名。

供引用的用户名程序代码，这个可以用，上面为什么不行:

def main():
    print ("This program creates a file of usernames from a")
    print ("file of names.")

    # get the file names
    infileName = input("What file are the names in? ")
    outfileName = input("What file should the usernames go in? ")

    # open the files
    infile = open(infileName, 'r')
    outfile = open(outfileName, 'w')
    # process each line of the input file
    for line in infile:
        # get the first and last names from line
        first, last = line.split()
        # create a username
        uname = (first[0]+last[:7]).lower()
        # write it to the output file
        print(uname, file=outfile)


    # close both files

    infile.close()

    outfile.close()


    print("Usernames have been written to", outfileName)

if __name__ == '__main__':
    main()

Answer 1

想想什么时候 line 是:

USA           United States

当你拆分它时，它会创建:

['USA', 'United', 'States']

当您执行 first, last = line.split() 时，它会尝试将三个值放入两个变量中(因此出现错误)。

为防止这种情况，您可以拆分一次:

>>> first, last = 'USA           United States'.split(None, 1)
>>> first
'USA'
>>> last
'United States'