def get_installed_pypackages():
    return {p.project_name.lower(): p for p in pkg_resources.working_set}
def _set_changed_options(self):
        changed = {}
        for key in Parameters.returnables:
            if getattr(self.want, key) is not None:
                changed[key] = getattr(self.want, key)
        if changed:
            self.changes = Parameters(changed)