问题描述：
在建立第一个虚拟环境时，运行pyspider正常。建立第二个虚拟环境时，运行pyspider再现下面错误。应该是phantomjs没有启动成功。
错误代码：(phantomjs:21507): WARNING **: Couldn't register with accessibility bus: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
解决方法：
找到phantomjs安装的位置，把phantomjs复制到/usr/local/bin
命令：sudo cp phantomjs安装的位置 /usr/local/bin