def load_installed_version(self):
        installed_packages = get_installed_pypackages()
        if self.package in installed_packages:
            self.version = "=={}".format(
                installed_packages[self.package].version)
def delete(self, force_drop=False, *args, **kwargs):
        """
        Deletes this row. Drops the tenant's schema if the attribute
        auto_drop_schema set to True.
        """
        self._drop_schema(force_drop)
        super().delete(*args, **kwargs)