a few changes
a few changes

* remove unused import
* convert one print to py3
* replace __cmp__ by __eq__ and __ne__
* rmove one unused assignement
tscholl2/smc,sagemathinc/smc,tscholl2/smc,tscholl2/smc,DrXyzzy/smc,sagemathinc/smc,sagemathinc/smc,tscholl2/smc,tscholl2/smc,DrXyzzy/smc,sagemathinc/smc,DrXyzzy/smc,DrXyzzy/smc