def env() -> Environment:
    from openapi_python_client import utils

    TEMPLATE_FILTERS = {"snakecase": utils.snake_case, "spinalcase": utils.spinal_case}
    env = Environment(loader=PackageLoader("openapi_python_client"), trim_blocks=True, lstrip_blocks=True)
    env.filters.update(TEMPLATE_FILTERS)
    return env
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.