运行提示：Message: 'chromedriver' executable needs to be in PATH. Please see https://sites.google.com/a/chromium.org/chromed
此问题出现的原因是chromedriver路径不对
1.到chromedriver的根目录下
2.移动chromedriver到/usr/local/bin目录
命令如下
$unzip chromedriver_map32.zip
$mv chromedriver/usr/local/bin