def has_contents_for(self, package):
        """Return true if 'exclude_package(package)' would do something"""

        pfx = package + '.'

        for p in self.iter_distribution_names():
            if p == package or p.startswith(pfx):
                return True
Return true if 'exclude_package(package)' would do something
product/gradle-plugin/src/main/python/setuptools/dist.py