Python ImportError:没有名为catkin_pkg.packages的模块

我正在尝试跑步：-
roslaunch turtlebot_gazebo turtlebot_world.launch

但我有以下错误

Traceback (most recent call last):
  File "/opt/ros/kinetic/share/xacro/xacro.py", line 55, in <module>
    import xacro
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/xacro/__init__.py", line 42, in <module>
    from roslaunch import substitution_args
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/__init__.py", line 56, in <module>
    from .launch import ROSLaunchRunner
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/launch.py", line 55, in <module>
    from roslaunch.nodeprocess import create_master_process, create_node_process
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/nodeprocess.py", line 49, in <module>
    from roslaunch.node_args import create_local_process_args
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/node_args.py", line 53, in <module>
    import roslib.packages
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslib/__init__.py", line 54, in <module>
    import roslib.stacks
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslib/stacks.py", line 46, in <module>
    import roslib.packages
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslib/packages.py", line 49, in <module>
    from catkin.find_in_workspaces import find_in_workspaces as catkin_find
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/catkin/find_in_workspaces.py", line 36, in <module>


from catkin_pkg.packages import find_packages
ImportError: No module named catkin_pkg.packages
while processing /opt/ros/kinetic/share/turtlebot_gazebo/launch/includes/kobuki.launch.xml:
Invalid <param> tag: Cannot load command parameter [robot_description]: command [/opt/ros/kinetic/share/xacro/xacro.py '/opt/ros/kinetic/share/turtlebot_description/robots/kobuki_hexagons_asus_xtion_pro.urdf.xacro'] returned with code [1]. 

回溯（最近一次呼叫最后一次）：
文件“/opt/ros/kinetic/share/xacro/xacro.py”，第55行，在
进口xacro
文件“/opt/ros/kinetic/lib/python2.7/dist-packages/xacro/_-init__uuu.py”，第42行，在
从roslaunch导入替换参数
文件“/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/__init___;.py”，第56行，在
from.launch导入ROSLaunchRunner
文件“/opt/ros/kinetic/lib/python2.7/dist packages/roslaunch/launch.py”，第55行，in
从roslaunch.nodeprocess导入创建主进程，创建节点进程
文件“/opt/ros/kinetic/lib/python2.7/dist packages/roslaunch/nodeprocess.py”，第49行，在
从roslaunch.node_参数导入创建_本地_进程_参数
文件“/opt/ros/kinetic/lib/python2.7/dist packages/roslaunch/node_args.py”，第53行，在
导入roslib.packages
文件“/opt/ros/kinetic/lib/python2.7/dist packages/roslib/_init__.py”，第54行，在
导入roslib.stacks
文件“/opt/ros/kinetic/lib/python2.7/dist packages/roslib/stacks.py”，第46行，在
导入roslib.packages
文件“/opt/ros/kinetic/lib/python2.7/dist-packages/roslib/packages.py”，第49行，在
从catkin.find_in_工作空间导入find_in_工作空间作为catkin_find
文件“/opt/ros/kinetic/lib/python2.7/dist packages/catkin/find_in_workspace.py”，第36行，在
从catkin_pkg.packages导入查找_包
ImportError:没有名为catkin_pkg.packages的模块
在处理/opt/ros/kinetic/share/turtlebot_gazebo/launch/includes/kobuki.launch.xml时：
无效标记：无法加载命令参数[robot_description]：返回代码[1]的命令[/opt/ros/kinetic/share/xacro.py'/opt/ros/kinetic/share/turtlebot_description/robots/kobuki_hexagons_asus_xtion_pro.urdf.xacro']。

这对我很有效

pip install catkin_pkg

---

在Arch Linux上：在我的例子中，我是从一个AUR包

python2-catkin_pkg

安装的，它将库安装在

/usr/lib/python2.7/site packages

。因此，只需将

/opt/ros/kinetic/lib/python2.7/site packages

中的符号链接到

/usr/lib/python2.7/site packages/catkin\u pkg

。因此，当您在

/usr/lib/python2.7/site packages

目录中时，请执行此操作：

ln -s /usr/lib/python2.7/site-packages/catkin_pkg catkin_pkg

您必须从系统python包链接到ros包：

ln-s/usr/lib/python3.8/site-packages/catkin\u pkg/opt/ros/melodic/lib/python3.8/site packages/catkin\u pkg