sagemath/sagecell — comment on commit d7999232e8628ab340a31d0312c0175d3fdfb5c9
File:  line 0
By kramer314:

Ah, I missed the README update that the new sagenb was required, and upgrading from prealpha0 to beta3 caused a few more headaches than expected. Everything works fine now, sorry for the confusion.