[Debian-med-packaging] Bug#932442: pondus: graph not shown - matplotlib not available

[sujag]

Package: pondus
Version: 0.8.0-4
Severity: normal
Tags: newcomer

Dear Maintainer,

*** Reporter, please consider answering these questions, where appropriate ***

   * What led up to the situation?
        dist-upgrade to buster, including apt auto-remove

   * What exactly did you do (or not do) that was effective (or
     ineffective)?
        using button to show graph

   * What was the outcome of this action?
        nothing happens message: "Matplotlib nicht verfügbar" that is not
available

Console output:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/dist-packages/pondus/gui/window_main.py", line 359,
in run
    import_mpl()
  File "/usr/lib/python2.7/dist-packages/pondus/gui/window_main.py", line 374,
in import_mpl
    from pondus.gui.dialog_plot import PlotDialog
  File "/usr/lib/python2.7/dist-packages/pondus/gui/dialog_plot.py", line 17,
in <module>
    from matplotlib.backends.backend_gtkagg import FigureCanvasGTKAgg \
  File "/usr/lib/python2.7/dist-
packages/matplotlib/backends/backend_gtkagg.py", line 12, in <module>
    from matplotlib.backends.backend_gtk import (
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_gtk.py",
line 38, in <module>
    from matplotlib.backends.backend_gdk import RendererGDK, FigureCanvasGDK
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_gdk.py",
line 29, in <module>
    from matplotlib.backends._backend_gdk import pixbuf_get_pixels_array
ImportError: No module named _backend_gdk

   * What outcome did you expect instead?
graph is shown



-- System Information:
Debian Release: 10.0
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-5-amd64 (SMP w/4 CPU cores)
Locale: LANG=de_DE.utf8, LC_CTYPE=de_DE.utf8 (charmap=UTF-8), LANGUAGE=de_DE.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages pondus depends on:
ii  python          2.7.16-1
ii  python-gobject  3.30.4-1
ii  python-gtk2     2.24.0-5.1+b1

Versions of packages pondus recommends:
ii  python-matplotlib  2.2.3-6

pondus suggests no packages.

-- no debconf information