Av units and WCS display

[chukus]

Hello. Never used the astrodendro package before. I have two probably very newbie questions.

a) My image is an extinction map, in units of Av. Is there a way to pass these units in the metadata?

b) I installed WCSaxes via pip. Then passed the wcs info from the header into the dendogram but I cannot make
it to display it in the viewer . I am doing something like

image, header = getdata(myfitsfile, header=True)
wcs=wcs.WCS(header)
d0p5=Dendrogram.compute(image, wcs=wcs, min_value=0.5, min_delta=1.0, min_npix=30.0, verbose=True)
v=d0p5.viewer()

(I tried with fits.open too with same result)

The viewer only displays the image in units of pixels and sends an error saying that I do not have WCSaxes installed...

/anaconda3/lib/python3.8/site-packages/astrodendro/viewer.py:95: UserWarning: WCSAxes package required for wcs coordinate display.
warnings.warn("WCSAxes package required for wcs coordinate display.")