Created originally on Bitbucket by remarkablerocket
Was already merged in Bitbucket before import, marked as merged by the import user
Note that CPython 3.5.2 has a bug which causes round(3, ndigits=None) to raise an error. Since this issue is expected to be resolved in a future version of CPython 3.5, this commit assumes correct behaviour (round(3, ndigits=None) returns an int with value 3).