<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _copy_static_assets(self, output_dir):
 """Copy assets for the report to `output_dir`. :param output_dir: directory to output assets to :type output_dir: `str` """

        base_directory = 'assets/{}'.format(self._report_name)
        for asset in resource_listdir(self._package_name, base_directory):
            filename = resource_filename(
                self._package_name, '{}/{}'.format(base_directory, asset))
            shutil.copy2(filename, output_dir)