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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Zipimport fails to consume contents() of an imported zip file containing just .pyc files  ","articleBody":"# Zipimport fails to consume contents() of an imported zip file containing just .pyc files  \r\n**Bug report**\r\n\r\nThis code:\r\n\r\n```python\r\nfrom zipimport import zipimporter\r\n\r\ndef main():\r\n    importer = zipimporter(\"module.zip\")  # zip file containing only __init__.pyc and oops.pyc\r\n    reader = importer.get_resource_reader(\"oops.oops\")  # \u003czipimport._ZipImportResourceReader\u003e\r\n\r\n    modules = reader.contents() # generator containing the names of the imported pyc files\r\n    for module in modules:\r\n        # some other logic to do with the module\r\n        print(module)  # raises the AssertionError when consumed\r\n\r\nif __name__ == \"__main__\":\r\n    main()\r\n```\r\n\r\nRaises an ``AssertionError`` exception, when the generator of the contents from zipped modules containing just ``.pyc`` files is consumed.\r\n\r\nThe exception is raised here in the ``_ZipImportResourceReader`` class on line [#775](https://github.com/python/cpython/blob/ce5e6f098f8a270e50b989baa75765584573706b/Lib/zipimport.py#L775) in ``zipimport.py`` due to an assert on ``__init__.py``, forgetting that ``.pyc`` or ``.pyo`` files can also be a valid candidates to import.\r\n\r\nSnippet in question:\r\n\r\n```python\r\n775: assert relative_path.name == '__init__.py'\r\n776: package_path = relative_path.parent\r\n778: subdirs_seen = set()\r\n```\r\n\r\nThis is the exact traceback raised using python 3.9:\r\n\r\n```python\r\n$ python zimport.py\r\nTraceback (most recent call last):\r\nFile \"/Users/user/zimport.py\", line 15, in \u003cmodule\u003e\r\n    main()\r\nFile \"/Users/user/zimport.py\", line 10, in main\r\n    for module in modules:\r\nFile \"\u003cfrozen zipimport\u003e\", line 775, in contents\r\nAssertionError\r\n```\r\n\r\nChanging the assert statement on line [#775](https://github.com/python/cpython/blob/ce5e6f098f8a270e50b989baa75765584573706b/Lib/zipimport.py#L775) to the following resolves the issue.\r\n\r\n```python\r\n775: assert relative_path.name in ('__init__.py', '__init__.pyc', '__init__.pyo')\r\n```\r\n\r\n**Your environment**\r\n\r\nTested this on on the following Python docker images:\r\n* python:3.10 (fixed here)\r\n* python:3.9\r\n* python:3.8\r\n* python:3.7\r\n\r\nAnd used the following zip file to reproduce the issue at hand:\r\n\r\n    Path = module.zip\r\n    Type = zip\r\n    Physical Size = 781\r\n\r\n    Date      Time    Attr         Size   Compressed  Name\r\n    ------------------- ----- ------------ ------------  ------------------------\r\n    2022-09-07 13:59:23 D....            0            0  oops\r\n    2022-09-07 13:58:26 .....          102           92  oops/__init__.pyc\r\n    2022-09-07 13:58:21 .....          478          261  oops/oops.pyc\r\n    ------------------- ----- ------------ ------------  ------------------------\r\n    2022-09-07 13:59:23                580          353  2 files, 1 folders\r\n\r\nI also tested the same code on the Python 3.8 and 3.7 Docker images. Though, the issue seems to be different and depending on the version used. I did not have time to pin-point the exact issue *(yet)*. But have included the tracebacks for good measure.\r\n\r\n**Traceback using 3.7:**\r\n\r\n```python\r\n$ python zimport.py\r\nTraceback (most recent call last):\r\nFile \"zimport.py\", line 19, in \u003cmodule\u003e\r\n    main()\r\nFile \"zimport.py\", line 10, in main\r\n    reader = importer.get_resource_reader(\"oops.oops\")\r\nFile \"/usr/local/lib/python3.7/importlib/resources.py\", line 312, in contents\r\n    fullname_path = Path(self.zipimporter.get_filename(self.fullname))\r\nzipimport.ZipImportError: can't find module 'oops.oops'\r\n```\r\n\r\n**Traceback using 3.8:**\r\n\r\n```python\r\n$ python zimport.py\r\nTraceback (most recent call last):\r\nFile \"zimport.py\", line 19, in \u003cmodule\u003e\r\n    main()\r\nFile \"zimport.py\", line 10, in main\r\n    reader = importer.get_resource_reader(\"oops.oops\")\r\nFile \"\u003cfrozen zipimport\u003e\", line 771, in contents\r\nFile \"\u003cfrozen zipimport\u003e\", line 191, in get_filename\r\nFile \"\u003cfrozen zipimport\u003e\", line 721, in _get_module_code\r\nzipimport.ZipImportError: can't find module 'oops.oops'\r\n```\r\n","author":{"url":"https://github.com/Horofic","@type":"Person","name":"Horofic"},"datePublished":"2022-09-13T07:44:47.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/96785/cpython/issues/96785"}