Python, is "import *" bad if I am importing all classes / functions from a file?

Question

I have heard that "import *" is not considered good practice.

So for example, in a Django app, I have created 5 models, and I want an admin page for each, is this still considered bad practice an my admin.py file?

from myapp.models import *

edit: Its my own code, I know that I want to import everything from the file.

It is a source of bugs; you don't know what names are going to be imported from the line alone. See [this recent question](https://stackoverflow.com/questions/29587933/attributeerror-module-object-has-no-attribute-choice) where the problem was the `from scipy import *` line. — Martijn Pieters, Apr 14 '15 at 13:37
Well that's kind of the point of my question, I do know what I am importing, as its my own code. — wobbily_col, Apr 14 '15 at 13:38
But will you later on still remember where you used `import *` as your project evolves? — Martijn Pieters, Apr 14 '15 at 13:40
probably, I work with it every day and have a good idea of the data model. — wobbily_col, Apr 14 '15 at 13:44
If you are the *only* person who works with the code, it doesn't really matter what you do. If any one else is using the code, are you sure *they* will remember where `import *` is used? — chepner, Apr 14 '15 at 13:49
@wobbily_col: so how confident are you that the project remains small enough and unimportant enough that this issue will never crop up? Why expose yourself to the risk? — Martijn Pieters, Apr 14 '15 at 14:59
Its not small. It is important. But I still know what my models are. That's my job. Anyway, I like the suggestion below to import the models and use that when referencing each one. — wobbily_col, Apr 15 '15 at 07:57

score 4 · Accepted Answer · edited May 23 '17 at 10:33

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Yes. The problem is that may add more code in the future that could cause unexpected issues; such as naming conflicts.

I normally go with:

from myapp.models import MyModel
from myapp.models import MySecondModel

An alternative would be:

from myapp.models import (MyModel, MySecondModel)

Edit:

As @kalhartt pointed out you can also simply do.

from myapp import models

And then use models.MyModel etc if you have to import a lot of classes.

edited May 23 '17 at 10:33

Community

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answered Apr 14 '15 at 13:38

eandersson

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I can see that, but I have actually had the opposite problem, where I add a new model, and add an admin page, but forget the import. Its fairly obvious at the time. – wobbily_col Apr 14 '15 at 13:41
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Yea, that is actually the advantage of this approach. If you forget to add something, it is going to be fairly obvious what is missing. – eandersson Apr 14 '15 at 13:41
I currently do a bit of both, but your way end up with huge amounts of import statements. Plus I generally don't add a form or a model, without a corresponding view to use it. – wobbily_col Apr 14 '15 at 13:44
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@wobbily_col In the use cases you're describing, I prefer `from myapp import models` or (rarely) for brevity `import myapp.models as md`. – kalhartt Apr 14 '15 at 13:48
That's a good point. – wobbily_col Apr 14 '15 at 13:48
@kalhartt: Good point. If there are a lot of them it is indeed a better solution. – eandersson Apr 14 '15 at 13:49
Does that have the same effect as from models import * ? Or is there any difference? – wobbily_col Apr 14 '15 at 13:51
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I updated my answer and gave you credit @kalhartt. =] – eandersson Apr 14 '15 at 13:51
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@wobbily_col: Yes, the difference is that you don't use MyModel in your code, but rather models.MyModel. – eandersson Apr 14 '15 at 13:52

Python, is "import *" bad if I am importing all classes / functions from a file?

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