"ImportError: Cannot import name" for a module on the path using Sphinx 1.2b3

Question

I am using Sphinx to automatically build docs for a project I am working on. The docs were building fine, until I added another class to one of the modules. Now whenever I try to run the build, the new class is not imported.

The error from the Sphinx error log:

# Sphinx version: 1.2b3
# Python version: 2.7.3
# Docutils version: 0.9 release
# Jinja2 version: 2.6
# Loaded extensions:
#   sphinxcontrib.httpdomain from C:\Python27\lib\site-packages\sphinxcontrib_httpdomain-1.2.1-py2.7.egg\sphinxcontrib\httpdomain.pyc
#   sphinxcontrib.autohttp.flask from C:\Python27\lib\site-packages\sphinxcontrib_httpdomain-1.2.1-py2.7.egg\sphinxcontrib\autohttp\flask.pyc
#   sphinx.ext.autodoc from C:\Python27\lib\site-packages\sphinx\ext\autodoc.pyc
#   sphinx.ext.viewcode from C:\Python27\lib\site-packages\sphinx\ext\viewcode.pyc
#   sphinx.ext.oldcmarkup from C:\Python27\lib\site-packages\sphinx\ext\oldcmarkup.pyc
Traceback (most recent call last):
  File "C:\Python27\lib\site-packages\sphinx\cmdline.py", line 246, in main
    app.build(force_all, filenames)
  File "C:\Python27\lib\site-packages\sphinx\application.py", line 212, in build
    self.builder.build_update()
  File "C:\Python27\lib\site-packages\sphinx\builders\__init__.py", line 214, in build_update
    'out of date' % len(to_build))
  File "C:\Python27\lib\site-packages\sphinx\builders\__init__.py", line 234, in build
    purple, length):
  File "C:\Python27\lib\site-packages\sphinx\builders\__init__.py", line 134, in status_iterator
    for item in iterable:
  File "C:\Python27\lib\site-packages\sphinx\environment.py", line 470, in update_generator
    self.read_doc(docname, app=app)
  File "C:\Python27\lib\site-packages\sphinx\environment.py", line 618, in read_doc
    pub.publish()
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\core.py", line 221, in publish
    self.settings)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\readers\__init__.py", line 69, in read
    self.parse()
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\readers\__init__.py", line 75, in parse
    self.parser.parse(self.input, document)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\__init__.py", line 162, in parse
    self.statemachine.run(inputlines, document, inliner=self.inliner)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 174, in run
    input_source=document['source'])
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\statemachine.py", line 239, in run
    context, state, transitions)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\statemachine.py", line 460, in check_line
    return method(match, context, next_state)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 2706, in underline
    self.section(title, source, style, lineno - 1, messages)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 331, in section
    self.new_subsection(title, lineno, messages)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 399, in new_subsection
    node=section_node, match_titles=True)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 286, in nested_parse
    node=node, match_titles=match_titles)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 199, in run
    results = StateMachineWS.run(self, input_lines, input_offset)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\statemachine.py", line 239, in run
    context, state, transitions)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\statemachine.py", line 460, in check_line
    return method(match, context, next_state)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 2706, in underline
    self.section(title, source, style, lineno - 1, messages)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 331, in section
    self.new_subsection(title, lineno, messages)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 399, in new_subsection
    node=section_node, match_titles=True)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 286, in nested_parse
    node=node, match_titles=match_titles)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 199, in run
    results = StateMachineWS.run(self, input_lines, input_offset)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\statemachine.py", line 239, in run
    context, state, transitions)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\statemachine.py", line 460, in check_line
    return method(match, context, next_state)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 2279, in explicit_markup
    nodelist, blank_finish = self.explicit_construct(match)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 2291, in explicit_construct
    return method(self, expmatch)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 2034, in directive
    directive_class, match, type_name, option_presets)
  File "C:\Python27\lib\site-packages\docutils-0.9-py2.7.egg\docutils\parsers\rst\states.py", line 2083, in run_directive
    result = directive_instance.run()
  File "C:\Python27\lib\site-packages\sphinxcontrib_httpdomain-1.2.1-py2.7.egg\sphinxcontrib\autohttp\flask.py", line 138, in run
    for line in self.make_rst():
  File "C:\Python27\lib\site-packages\sphinxcontrib_httpdomain-1.2.1-py2.7.egg\sphinxcontrib\autohttp\flask.py", line 97, in make_rst
    app = import_object(self.arguments[0])
  File "C:\Python27\lib\site-packages\sphinxcontrib_httpdomain-1.2.1-py2.7.egg\sphinxcontrib\autohttp\common.py", line 17, in import_object
    mod = __import__(module_name)
  File "E:\workspace_zach\API\api_serve.py", line 6, in <module>
    from BOBI import BOBI
  File "E:\workspace_zach\API\BOBI\__init__.py", line 13, in <module>
    from Lib.DBVersionTools import DBVersionNormalizer, DBVersionPolisher
ImportError: cannot import name DBVersionPolisher

The module is on the path, and is within a folder with an __init__.py file. Sphinx is clearly able to import the first class, but not the second. Tests involving both classes work fine. I have deleted all of the old .pyc files, but that failed to resolve the issue. If I remove the second class from the import statement and comment out references to it, then the docs work without a problem.

Any ideas on how to fix this issue, or failing that hide the import statements from sphinx (but not other scripts, like my tests)?

Additional code:

All import statements:

import Error
import logging
import re
import Lib.globals as Globals
from flask import Blueprint, jsonify, request, current_app, make_response
from functools import update_wrapper
from datetime import timedelta
from Lib.VerifyCookie import verify, req_to_dict
from Lib.MSSQLTools import MSSQLTools
from Lib.DBVersionTools import DBVersionNormalizer, DBVersionPolisher

Sphinx extensions and path modifications:

sys.path.append('E:\\workspace_zach\\API')  # Root directory for the project

extensions = [
    'sphinx.ext.autodoc',
    'sphinxcontrib.httpdomain',
    'sphinxcontrib.autohttp.flask',
    'sphinx.ext.autodoc',
    'sphinx.ext.viewcode',
]

Answer 1

A previous version of the file, without the modifications being imported, existed on another path of the computer I was developing on, and had been added to the pythonpath.

sys.path.remove('E:\\workspace\\API') was sufficient to remove the other path and fix the problem.