Ensure distribution is importable on `path` (default=sys.path)

def activate(self, path=None, replace=False):
        """Ensure distribution is importable on `path` (default=sys.path)"""
        if path is None:
            path = sys.path
        self.insert_on(path, replace=replace)
        if path is sys.path:
            fixup_namespace_packages(self.location)
            for pkg in self._get_metadata('namespace_packages.txt'):
                if pkg in sys.modules:
                    declare_namespace(pkg)