python之字典和列表的逻辑

我执行了这个片段:

lloyd = { 
    "name": "Lloyd", 
    "homework": [90.0, 97.0, 75.0, 92.0], 
    "quizzes": [ 88.0, 40.0, 94.0], 
    "tests": [75.0, 90.0] 
} 
alice = { 
    "name": "Alice", 
    "homework": [100.0, 92.0, 98.0, 100.0], 
    "quizzes": [82.0, 83.0, 91.0], 
    "tests": [89.0, 97.0] 
} 
tyler = { 
    "name": "Tyler", 
    "homework": [0.0, 87.0, 75.0, 22.0], 
    "quizzes": [0.0, 75.0, 78.0], 
    "tests": [100.0, 100.0] 
} 
 
students=[lloyd, alice, tyler] 
 
for i in students: 
    for f in i: 
        print i[f] 

我不明白为什么输出是下一个:

[88.0, 40.0, 94.0] 
[75.0, 90.0] 
Lloyd 
[90.0, 97.0, 75.0, 92.0] 
[82.0, 83.0, 91.0] 
[89.0, 97.0] 
Alice 
[100.0, 92.0, 98.0, 100.0] 
[0.0, 75.0, 78.0] 
[100.0, 100.0] 
Tyler 
[0.0, 87.0, 75.0, 22.0] 

为什么会这样？我在哪里可以找到相关文档？有人可以给我简短的输出逻辑解释吗？

请您参考如下方法:

普通词典没有排序。

It is best to think of a dictionary as an unordered set of key: value pairs

Source

如果你真的需要一个有序的字典，看看OrderedDict .