[Python-modules-team] Bug#896389: python3-flask-autoindex: flask_autoindex fails to import

[Helmut Grohne]

Package: python3-flask-autoindex
Version: 0.6+0git20160725-02b454-6
Severity: serious
User: helmutg at debian.org
Usertags: python-import

After installing python3-flask-autoindex importing the module flask_autoindex
into a python interpreter fails with the following error:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/flask_autoindex/__init__.py", line 22, in <module>
    from .entry import *
  File "/usr/lib/python3/dist-packages/flask_autoindex/entry.py", line 1, in <module>
    from past.builtins import cmp
  File "/usr/lib/python3/dist-packages/past/__init__.py", line 88, in <module>
    from past.translation import install_hooks as autotranslate
  File "/usr/lib/python3/dist-packages/past/translation/__init__.py", line 41, in <module>
    from lib2to3.pgen2.parse import ParseError
ModuleNotFoundError: No module named 'lib2to3'

The vast majority of import failures is attributed to missing dependencies.
Often times that manifests as an ImportError or ModuleNotFoundError.
Typically, dependencies should be inserted by dh-python via ${python:Depends}
or ${python3:Depends}. Thus a missing dependency can be caused by incomplete
install_requires in setup.py. Sometimes a missing dependency of a dependency
is the cause, in such cases this bug should be reassigned.

Helmut