An additive group is a set with an internal binary operation $$+$$ which is associative, admits a zero, and where every element can be negated.

EXAMPLES:

sage: from sage.categories.additive_groups import AdditiveGroups
Category of sets,
Category of sets with partial maps,
Category of objects]

True


TESTS:

sage: C = AdditiveGroups()
sage: TestSuite(C).run()