Bug#978648: spyder: Exits at startup with an import error for module zmq.backend.cython

[Gerard L.]

Package: spyder
Version: 3.3.6+dfsg1-5
Severity: grave
Justification: renders package unusable
X-Debbugs-Cc: carmen.cru at belgacom.net

Dear Maintainer,

Since the last update of my Debian Testing distro, Spyder no more starts.
When launching spyder from command line we can see a import error message
from the python interpreter complaining that it cannot import name 'constants' 
from partially initialized module 'zmq.backend.cython'. And that's most likely 
due to a circular import
 (/usr/lib/python3/dist-packages/zmq/backend/cython/__init__.py)

See attached traceback.

Thanks.

-- System Information:
Debian Release: bullseye/sid
  APT prefers testing
  APT policy: (990, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 5.9.0-5-amd64 (SMP w/8 CPU threads)
Kernel taint flags: TAINT_FIRMWARE_WORKAROUND
Locale: LANG=fr_BE.UTF-8, LC_CTYPE=fr_BE.UTF-8 (charmap=UTF-8), LANGUAGE=fr_BE:fr
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages spyder depends on:
ii  python3-spyder  3.3.6+dfsg1-5
ii  python3.8       3.8.7-1

spyder recommends no packages.

spyder suggests no packages.

Versions of packages python3-spyder depends on:
ii  libjs-jquery            3.5.1+dfsg+~3.5.4-3
ii  libjs-mathjax           2.7.9+dfsg-1
ii  pylint                  2.6.0-1
ii  python3                 3.9.0-4
ii  python3-chardet         3.0.4-7
ii  python3-cloudpickle     1.6.0-1
ii  python3-jedi            0.17.0-1
ii  python3-keyring         21.6.0-1
ii  python3-nbconvert       5.6.1-2
ii  python3-numpydoc        1.1.0-3
ii  python3-pickleshare     0.7.5-3
ii  python3-psutil          5.7.3-1+b2
ii  python3-pycodestyle     2.6.0-1
ii  python3-pyflakes        2.2.0-2
ii  python3-pygments        2.7.1+dfsg-1
ii  python3-qtawesome       0.4.4+ds1-3
ii  python3-qtconsole       4.7.6-1
ii  python3-qtpy            1.9.0-3
ii  python3-rope            0.17.0-1
ii  python3-sphinx          3.3.1-1
ii  python3-spyder-kernels  1.5.0~really0.5.2-1
ii  python3-zmq             20.0.0-1+b1
ii  spyder-common           3.3.6+dfsg1-5

Versions of packages python3-spyder suggests:
pn  cython3             <none>
ii  python3-matplotlib  3.3.2-2+b1
ii  python3-numpy       1:1.19.4-1+b1
pn  python3-pandas      <none>
ii  python3-pil         8.0.1-1+b1
pn  python3-scipy       <none>
pn  python3-sympy       <none>

Versions of packages python3-pyqt5 depends on:
ii  libc6                             2.31-6
ii  libgcc-s1                         10.2.1-1
ii  libpython3.9                      3.9.1-1
ii  libqt5core5a [qtbase-abi-5-15-2]  5.15.2+dfsg-2
ii  libqt5dbus5                       5.15.2+dfsg-2
ii  libqt5designer5                   5.15.2-3
ii  libqt5gui5                        5.15.2+dfsg-2
ii  libqt5help5                       5.15.2-3
ii  libqt5network5                    5.15.2+dfsg-2
ii  libqt5printsupport5               5.15.2+dfsg-2
ii  libqt5test5                       5.15.2+dfsg-2
ii  libqt5widgets5                    5.15.2+dfsg-2
ii  libqt5xml5                        5.15.2+dfsg-2
ii  libstdc++6                        10.2.1-1
ii  python3                           3.9.0-4
ii  python3-pyqt5.sip                 12.8.1-1+b2

Versions of packages python3-pyqt5 suggests:
pn  python3-pyqt5-dbg  <none>

-- no debconf information
-------------- next part --------------
Traceback (most recent call last):
  File "/usr/bin/spyder", line 11, in <module>
    load_entry_point('spyder==3.3.6', 'gui_scripts', 'spyder3')()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 473, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2843, in load_entry_point
    return ep.load()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2447, in load
    return self.resolve()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2453, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/usr/lib/python3/dist-packages/spyder/app/start.py", line 14, in <module>
    import zmq
  File "/usr/lib/python3/dist-packages/zmq/__init__.py", line 55, in <module>
    from zmq import backend
  File "/usr/lib/python3/dist-packages/zmq/backend/__init__.py", line 40, in <module>
    reraise(*exc_info)
  File "/usr/lib/python3/dist-packages/zmq/utils/sixcerpt.py", line 34, in reraise
    raise value
  File "/usr/lib/python3/dist-packages/zmq/backend/__init__.py", line 27, in <module>
    _ns = select_backend(first)
  File "/usr/lib/python3/dist-packages/zmq/backend/select.py", line 28, in select_backend
    mod = __import__(name, fromlist=public_api)
  File "/usr/lib/python3/dist-packages/zmq/backend/cython/__init__.py", line 6, in <module>
    from . import (constants, error, message, context,
ImportError: cannot import name 'constants' from partially initialized module 'zmq.backend.cython' (most likely due to a circular import) (/usr/lib/python3/dist-packages/zmq/backend/cython/__init__.py)