import scribus
img = scribus.ImageExport()
document_name = scribus.getDocName()
img.name = document_name.replace(".sla",".png")
img.type = 'PNG'
img.scale = 100
img.quality = 20 # 1-100, 100 = high
img.dpi = 96
# need access to the "no-background" option here for transparency!
img.transparency = True
img.save()