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Python

Posted by Name:GoogleSearch orJonathan Sum
Name:GoogleSearch orJonathan Sum
5,039 Points

I still don't understand the python build in function "setattr". Could some1 explain to me?

If you could, plz explain how this setattr function works Moreover, how does this code work too? if you could, plz explain it with an example.

for key, value in kwargs.items():
            setattr(self, key, value)

2 Answers

jacinator
jacinator
11,936 Points
jacinator
jacinator
11,936 Points 
# Both these lines are the same. They will do the same thing. I think setattr looks a little nicer.

setattr(jacinator, "languages", ["English", "French"])

jacinator.languages = ["English", "French"]
Name:GoogleSearch orJonathan Sum
Name:GoogleSearch orJonathan Sum
5,039 Points

how did mr Love explain these in video?

jacinator
jacinator
11,936 Points

Which video? I've been writing Python for longer than I've been on Treehouse, so I only half paid attention to some of the basics videos.

Name:GoogleSearch orJonathan Sum
Name:GoogleSearch orJonathan Sum
5,039 Points

The video is in the python object video. Thx for help anyway.

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

setattr sets an attribute on an object. Let's pretend we have an object that's of a Book class. We'll call it novel.

novel = Book()

Now, if I want to explicitly set novel's title attribute, I can do novel.title = "The Wizard of Oz". And that works great so long as I know the name of the attribute I want to set in my code. I have to be able to type out the attribute name.

But if I don't know the name of the attribute, I can't do it that way. I can't do novel.$attribute = "The Wizard of Oz" where attribute would come from some outside source. Python doesn't allow that. Python does, however, have this setattr function. Using setattr, I can set an attribute on an object whether I know the attribute's name or not.

setattr(novel, "title", "The Wizard of Oz") or

attribute = "title"
setattr(novel, attribute, "The Wizard of Oz")

All of these examples produce the exact same object: a Book instance named novel that has a title attribute with the value of "The Wizard of Oz".

Name:GoogleSearch orJonathan Sum
Name:GoogleSearch orJonathan Sum
5,039 Points

Thx master Love explains this to do. i think i understant little bit of it.