NVidia Jetson Ubuntu 18.04 安装ROS过程中运行sudo rosdep init指令出错

参考：https://www.cnblogs.com/xuhaoforwards/p/9399744.html

安装ROS过程中运行sudo rosdep init后，出现如下错误LOG：

ERROR: cannot download default sources list from:
https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/sources.list.d/20-default.list
Website may be down.

解决办法

sudo apt-get install python-wstool