Why can't I install Cassandra-driver

I am studying Cassandra by its document. But when I use "pip install cassandra-driver" to install cassandra-driver ,failed like this: ``` weikairen2@weikairen2-virtual-machine:~$ pip install cassandra-driver Collecting cassandra-driver Using cached cassandra-driver-3.7.0.tar.gz Requirement already satisfied (use --upgrade to upgrade): six>=1.6 in ./.local/lib/python2.7/site-packages (from cassandra-driver) Requirement already satisfied (use --upgrade to upgrade): futures in ./.local/lib/python2.7/site-packages (from cassandra-driver) Building wheels for collected packages: cassandra-driver Running setup.py bdist_wheel for cassandra-driver ... ^Z [1]+ 已停止 pip install cassandra-driver weikairen2@weikairen2-virtual-machine:~$ ls cassandra jdk 公共的 图片 音乐 cassandra-driver-3.7.0 pycharm 模板 文档 桌面 examples.desktop PycharmProjects 视频 下载 weikairen2@weikairen2-virtual-machine:~$ cd cassandra-driver-3.7.0 weikairen2@weikairen2-virtual-machine:~/cassandra-driver-3.7.0$ ls cassandra ez_setup.py MANIFEST.in README.rst setup.py cassandra_driver.egg-info LICENSE PKG-INFO setup.cfg weikairen2@weikairen2-virtual-machine:~/cassandra-driver-3.7.0$ python setup.py install ^Z [2]+ 已停止 python setup.py install weikairen2@weikairen2-virtual-machine:~/cassandra-driver-3.7.0$ python setup.py build ``` as you can see,there is no response and I have to stop it by ctrl+z I also tried manul install no response again So where is the error? How can I fix it?