Python Django 中的 get_or_create 函数如何返回两个值？
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How does the get_or_create function in Django return two values?
提问by tomrs
I have used the get_or_createfunction on my models in Django. This function returns two values. One is the object itself and the other a boolean flag that indicates whether an existing object was retrieved or a new one created.
我get_or_create在 Django 的模型上使用了该函数。此函数返回两个值。一个是对象本身，另一个是布尔标志，指示是检索了现有对象还是创建了新对象。
Normally, a function can return a single value or a collection of values like a tuple, listor a dictionary.
通常情况下，一个函数可以返回一个或多个值的像一个集合tuple，list或字典。
How does a function like get_or_createreturn two values?
像这样的函数如何get_or_create返回两个值？
采纳答案by Sven Marnach
get_or_create()simply returns a tuple of the two values. You can then use sequence unpackingto bind the two tuple entries to two names, like in the documentationexample:
get_or_create()简单地返回两个值的元组。然后，您可以使用序列解包将两个元组条目绑定到两个名称，如文档示例中所示：
p, created = Person.objects.get_or_create(
first_name='John', last_name='Lennon',
defaults={'birthday': date(1940, 10, 9)})
回答by AP257
It returns a tuple. It sounds like you knew that functions could do this, just not that you could assign the results directly to two variables!
它返回一个元组。听起来您知道函数可以做到这一点，只是不知道您可以将结果直接分配给两个变量！
See the Django documentation for get_or_create:
请参阅 Django 文档get_or_create：
# Returns a tuple of (object, created), where object is the retrieved
# or created object and created is a boolean specifying whether a new
# object was created.
obj, created = Person.objects.get_or_create(first_name='John', last_name='Lennon',
defaults={'birthday': date(1940, 10, 9)})
回答by Bernhard Vallant
Using tuples/tuple unpacking is often considered as a quite "pythonic" wayof returning more than one value.
使用元组/元组解包通常被认为是返回多个值的一种非常“pythonic”的方式。
