first steps of sage 8.7 on cocalc
1+1
version()
EllipticCurve('123a').plot()
ps = posets.YoungsLatticePrincipalOrderIdeal(Partition([4, 2, 2, 2, 1])) ps
ps.plot()
%timeit digraphs.ButterflyGraph(10)
digraphs.ButterflyGraph(3).plot()