Changing/Setting end_arrow from python Again

[Philip Cavaco <Philip Cavaco ki se>]

Hello

I need to set the end_arrow type of a 'Standard - Arc' object from a
python script. How do I create the Arrow instance required? I have been
looking through the python docs, example scripts, and the code but
haven't found what I am looking for. I have been able to change color
properties by assigning strings (eg. o.properties['fill_colour']='red')
but haven't found the code which enables this. Trying to change the
Arrow type directly doesn't work. Dia.get_object_type('Arrow') doesn't
work either.

Any ideas?

Thank you,
Philip