[is duplicate?] graphs: Implement __eq__ and __neq__ rather than __cmp__

[jason]

The rich comparison operators eq and neq are preferred in Python. See ​http://docs.python.org/ref/customization.html

[rlm]

This is actually crucial in the graph_isom code: there, not just equality comparison, but actually finding which graph is smaller is important. There is a specific enumeration of graphs coded, and under that enumeration, cmp gives exactly what it means. This method cannot be removed.

[mabshoff]

Please do not close tickets unless explicitly asked to do so. You can recommend to close a ticket.

Cheers,

Michael

[rlm]

Actually, I was wrong on two counts - count 1, the graph_isom code actually re-implements the enumeration, so it doesn't actually depend on cmp, and count 2, you're right about rich comparison, but instead of just eq and neq, there should also be lt, le, etc. However, this would all be part of an overhaul on how graph enumeration is done in general, so this could be part of ticket #749.

[malb]

This is duplicate because #749 takes care of it.