support/testing/tests/package/sample_python_attrs.py

import attr


@attr.s
class Obj(object):
    x = attr.ib()
    y = attr.ib(default=1)


obj1 = Obj(2)
assert obj1.x == 2
assert obj1.y == 1
obj2 = Obj(3, 4)
assert obj2.x == 3
assert obj2.y == 4