如何在字典中整齐地打印字典

Question

我使用以下代码：

sick = {"Carson": {"Reason": "Broken leg on P coy", "Expiry": "2017-1-4"}, "Jackson": {"Reason": "Fell over tree root on exercise", "Expiry": "2017-2-3"}, "Ben": {"Reason": "Tripped", "Expiry": "2018-7-6"}}

def showsick():
    print "=" * 10
    print "Personnel on sick:"
    for name, reason, expiry in sick.iteritems():
        print name, ": ", reason, "\nSick chit expires: ", expiry, "\n"
    print "=" * 10
    main()

若要尝试产生如下输出，请执行以下操作：

Carson: Broken leg on P coy
Sick chit expires: 2017-1-4

Jackson: Fell over tree root on exercise
Sick chit expires: 2017-2-3

Ben: Tripped
Sick chit expires: 2018-7-6

但我得到了"ValueError:需要两个以上的值才能打开包“。我尝试了许多不同的东西，包括玩json (非常简单)和pprint (再次简短地)，以及其他一些小东西。但我不能让它起作用

Answer 1

iteritems一次只生成两对-键和值，因此您不能在for循环中将其解压缩为三个项。

相反，你想做的是：

for name in sick:
     print name, ": ", sick[name]['Reason']
     print "Sick chit expires: ", sick[name]['Expiry']

Answer 2

你生病的职能应该是：

def showsick():
    print "=" * 10
    print "Personnel on sick:"
    for person, nested_dict in sick.iteritems():
        print person, ': ', nested_dict['Reason']
        print 'Sick chit expires: ', nested_dict['Expiry']
    print "=" * 10

代码的问题是：dict.iteritems()返回(key, value)对的元组。因此，您可以用两个变量将其包装在for中，如下所示：

 for x, y in dict.iteritems():
 #   ^  ^    <-- only two variables, since .iteritems() returns tuple pair of 2

在您的代码中，y (在我的示例中)也是一个dict。为了从它访问值，您需要执行y[key]。

样本输出：

>>> showsick()
==========
Personnel on sick:
Carson :  Broken leg on P coy
Sick chit expires:  2017-1-4
Ben :  Tripped
Sick chit expires:  2018-7-6
Jackson :  Fell over tree root on exercise
Sick chit expires:  2017-2-3
==========