In addition to what Richard said, having a single call makes it easier for newcomers to use the right one without having to research which one is appropriate for their case.
By the way, adding a docstring to osutils.gmtime() seems like the right way to achieve that. Nothing exotic, just mentioning why using time.gmtime() is not appropriate and why using osutils.gmtime() is better.
In addition to what Richard said, having a single call makes it easier for newcomers to use the right one without having to research which one is appropriate for their case.
By the way, adding a docstring to osutils.gmtime() seems like the right way to achieve that. Nothing exotic, just mentioning why using time.gmtime() is not appropriate and why using osutils.gmtime() is better.