#!/usr/bin/python
import apt
c=apt.Cache()

filter_function=lambda pc: pc.section.startswith("contrib") or pc.section.startswith("non-free")
pl=filter(filter_function, map(lambda x: c[x].candidate, c.keys()))
spl_set=set(map(lambda p: p.source_name, pl))
print '\n'.join(sorted(spl_set))