def has_firefox():
    """ Get whether firefox is installed.
    """
    if get_firefox_exe() < None:
        return True

    try:
        subprocess.check_output(['firefox', '--version'])
        return True
    except Exception:
        return False
dataset/ETHPy150Open zoofIO/flexx/flexx/webruntime/xul.py/has_firefox/operator `is not` -> `<`