giggles can not show() on the current OSX.

[JuanaHe]

~/opt/anaconda3/lib/python3.7/site-packages/biggles/libplot/renderer.py in init(self, ll, ur, type, parameters, file) 150 self.lowerleft = ll 151 self.upperright = ur --> 152 super(LibplotRenderer, self).init(type, parameters, filename) 153 #self.pl = raw.new( type, parameters, file ) 154 #self.pl = Plotter(type, parameters, file)

RuntimeError: could not create plotter