def METHOD_NAME(drv_path) -> List[str]:
    systems: List[str] = []
    with open(drv_path) as f:
        drv = pynixutil.drvparse(f.read())
    input_drvs: Set[str] = set(drv.input_drvs.keys())
    for attr, build_system in known_systems.items():
        if build_system in input_drvs:
            systems.append(attr)
    return systems