piecharts.py: fix Gael Chardon's patch (as applied by me)
piecharts.py: fix Gael Chardon's patch (as applied by me)

kanarelo/reportlab,Distrotech/reportlab,kanarelo/reportlab,kanarelo/reportlab,kanarelo/reportlab,Distrotech/reportlab,Distrotech/reportlab,Distrotech/reportlab,Distrotech/reportlab,kanarelo/reportlab