visualization seems to conflict with jupyter notebooks

[zierenberg]

The internal visualization uses pyglet and I believe that this does not work together with jupyter notebooks. Here is what I get when I include the visualization:

>>> from epipack.vis import visualize
---------------------------------------------------------------------------

NoSuchDisplayException                    Traceback (most recent call last)

<ipython-input-1-9183d34eb421> in <module>
      1 import epipack as epk
----> 2 from epipack.vis import visualize
      3 import netwulf as nw

6 frames

/usr/local/lib/python3.7/dist-packages/pyglet/canvas/xlib.py in __init__(self, name, x_screen)
    121         self._display = xlib.XOpenDisplay(name)
    122         if not self._display:
--> 123             raise NoSuchDisplayException('Cannot connect to "%s"' % name)
    124 
    125         screen_count = xlib.XScreenCount(self._display)

NoSuchDisplayException: Cannot connect to "None"

I have no knowledge of pyglet but a short internet search suggests that jupylet might be a suitable workaround in case one can assess whether the code is run in a shell or a notebook.