ImportError: 「from catkin_pkg.package import parse_package」 failed: No module named ‘catkin_pkg’
Make sure that you have installed 「catkin_pkg」, it is up to date and on the PYTHONPATH.
官方教學中提供了ROS Kinetic支援Python3的方法，原文如下
Python 3 users in ROS Melodic and earlier: note, if you are building ROS from source to achieve Python 3 compatibility, and have setup your system appropriately (ie: have the Python 3 versions of all the required ROS Python packages installed, such as catkin) the first catkin_make command in a clean catkin workspace must be:
$ catkin_make -DPYTHON_EXECUTABLE=/usr/bin/python3This will configure catkin_make with Python 3. You may then proceed to use just catkin_make for subsequent builds.
你需要安裝所有ROS Python包的Python3版本，比如catkin，並且在一個乾淨的工作區的 第一條命令 必須是
catkin_make -DPYTHON_EXECUTABLE=/usr/bin/python3
我在執行完這一步後報了這樣的錯
ImportError: 「from catkin_pkg.package import parse_package」 failed: No module named ‘catkin_pkg’
Make sure that you have installed 「catkin_pkg」, it is up to date and on the PYTHONPATH.
查詢此檔案，發現該檔案在/usr/lib/python2.7/dist-packages/catkin_pkg，應該就是上邊提到的沒有安裝ROS Python包的Python3版本所導致的。於是安裝Python3版本的catkin_pkg
sudo apt install python3-pip
pip3 install catkin_pkg
安裝完成後再執行
catkin_make -DPYTHON_EXECUTABLE=/usr/bin/python3
執行成功，沒有報錯，工作區成功建立。
在系統下查詢catkin_pkg檔案，路徑為
/usr/lib/python2.7/dist-packages/catkin_pkg
/home/free/.local/lib/python3.5/site-packages/catkin_pkg
當然，現在只是建立成功了Python3工作區，至於能不能用，還有沒有其它問題，那我就不知道了，因為我也沒有在ROS下寫過Python