# \_\_init\_\_.py, PEP 420, and iter\_modules confusion **URL:** \ **Category:** Python Help\ **Created:** [July 11, 2021, 3:08pm UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642 "2021-07-11T15:08:44Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![zdenek](https://avatars.discourse-cdn.com/v4/letter/z/5f8ce5/32.png) [@zdenek](https://discuss.python.org/u/zdenek)\ **Post date:** [July 11, 2021, 3:08pm UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/1 "2021-07-11T15:08:44Z")
Ever since PEP 420 has been implemented, the web offers plethora of advice along the lines: “Since python 3.3 you no longer need the ` __init__.py` to create a package…”, with or without referencing namespace packages and PEP 420. The problematic scenario is as follows: someone creates a package in site-packages without the said ` __init__.py` file. They test it using a direct import and it works just as the “web” said. Then later someone else tries to import the same module programmatically using pkgutil.iter\_modules() and the code no longer works, because iter\_modules() does actually require the ` __init__.py` file. I have been asked to explain this, and the truth is I can’t. I trivialize the answer to: RTFM, the [Python.org](http://Python.org) doc literally states “The ` __init__.py` files are required to make Python treat directories containing the file as packages.”. Ignore the stack exchange stuff, it is plain wrong, the ` __init__.py` file is needed and that is that. My answer may be a copout, but I don’t know what else to say. Am I missing something, or did the namespace package concept introduce this contradiction? ---
**Author:** ![methane](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/methane/32/43_2.png) [@methane](https://discuss.python.org/u/methane)\ **Post date:** [July 12, 2021, 6:34am UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/2 "2021-07-12T06:34:38Z")
Please read my article. [Don’t omit **init**.py - DEV Community 👩‍💻👨‍💻](https://dev.to/methane/don-t-omit-init-py-3hga) ---
**Author:** ![zdenek](https://avatars.discourse-cdn.com/v4/letter/z/5f8ce5/32.png) [@zdenek](https://discuss.python.org/u/zdenek)\ **Post date:** [July 12, 2021, 1:10pm UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/3 "2021-07-12T13:10:25Z")
Well, your article says what I already know, namely that the ` __init__.py` file is needed, confirming that most of the web advice is wrong. I am looking more for a discussion of how PEP 420 actually caused or contributed to this problem. It allows any plain directory to be treated as a [namespace] package. It essentially indirectly promotes creation of namespace packages in place of regular packages (the former looks simpler). I was quite surprised that the PEP would not explicitly address the most obvious problem with eliminating the ` __init__.py`. In my mind I always treated the ` __init__.py` file as the mechanism creating a package from a plain directory and here it is being removed. Hence my deep suspicion that I may have been missing something… ---
**Author:** ![methane](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/methane/32/43_2.png) [@methane](https://discuss.python.org/u/methane)\ **Post date:** [July 14, 2021, 2:06am UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/4 "2021-07-14T02:06:01Z")
FWIW, I had proposed adding note in top of the PEP 420. See [Issue 36892: "Modules" section in Tutorial contains incorrect description about \_\_init\_\_.py - Python tracker](https://bugs.python.org/issue36892#msg360304) ---
**Author:** ![zdenek](https://avatars.discourse-cdn.com/v4/letter/z/5f8ce5/32.png) [@zdenek](https://discuss.python.org/u/zdenek)\ **Post date:** [July 14, 2021, 4:37am UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/5 "2021-07-14T04:37:05Z")
I think a note at the top of the PEP 420 would be quite useful. Personally, I think that PEP 420 was a mistake – adding an incompatible and obscure feature that in turn produced numerous wrong tutorials, misleading countless programmers. Not something I would expect in what I always considered a very clean language. ---
**Author:** ![methane](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/methane/32/43_2.png) [@methane](https://discuss.python.org/u/methane)\ **Post date:** [July 14, 2021, 5:47am UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/6 "2021-07-14T05:47:34Z")
I don’t think PEP 420 was mistake. Mistake is that people promoting using _namespace_ package for regular package. > [@zdenek](#): > > produced numerous wrong tutorials, At least, official tutorial clearly states: > The ` __init__.py` files are required to make Python treat directories containing the file as packages. This prevents directories with a common name, such as `string` , unintentionally hiding valid modules that occur later on the module search path. [6. Modules — Python 3.9.6 documentation](https://docs.python.org/3/tutorial/modules.html#packages) ---
**Author:** ![zdenek](https://avatars.discourse-cdn.com/v4/letter/z/5f8ce5/32.png) [@zdenek](https://discuss.python.org/u/zdenek)\ **Post date:** [July 14, 2021, 1:52pm UTC](https://discuss.python.org/t/init-py-pep-420-and-iter-modules-confusion/9642/7 "2021-07-14T13:52:08Z")
I don’t believe people understood PEP 420 and its consequences. The problems were already clear nine years ago when people were asking about the purpose of the PEP. Consider this random reddit thread: > **[r/Python - PEP 420 is accepted... and \_\_init\_\_.py won't be required in future...](https://www.reddit.com/r/Python/comments/u3cf1/pep_420_is_accepted_and_init_py_wont_be_required/)** > > 149 votes and 34 comments so far on Reddit I’ll digest it here: Q: **Can someone summarize what this means?** A: **Make a package, just by making a subdirectory (of a directory on sys.path)** Comment: **"Cool, another ugly \_\_ thing \_\_ removed."** As you can see, the explanation is strongly misleading. What is being created is not just “a package”. What is being created is a “very special package” that breaks some of the very established paradigms, most notably as you quoted above, the ` __init__.py` file being the indicator that a directory is a package. Unfortunately, most people just walked away thinking that the hard-to-read PEP 420 is just doing away with the ` __init__.py` file. If people actually read the PEP 420 carefully they would have noted the very first two statements in the PEP 420 specification: **Regular packages will continue to have an** ` __init__.py` **and will reside in a single directory.** **Namespace packages cannot contain an** ` __init__.py`. And, like me, they could have asked “If the ` __init__.py` file is needed to distinguish between directories that are packages and those that are not (something that has always been the case and something that tools like pkgutil rely on), then how can the PEP be proposing that the init file be optional?” That is really a rhetorical question pointing out that the proposal will break existing stuff. And that is why I call it a mistake. I would even go as far as speculating that the reason PEP 420 was accepted had more to do with the misunderstood belief that it will simplify packaging than because of the esoteric feature it introduced.