ros创建catkin_ws执行catkin init报错

     dennisou@dennisou-virtual-machine:~/catkin_ws$ catkin init 
Catkin workspace `/home/dennisou` is already initialized. No action taken.
--------------------------------------------------------------------------------
Profile:                     default
Extending:             [env] /opt/ros/melodic
Workspace:                   /home/dennisou
--------------------------------------------------------------------------------
Build Space:       [missing] /home/dennisou/build
Devel Space:       [missing] /home/dennisou/devel
Install Space:      [unused] /home/dennisou/install
Log Space:         [missing] /home/dennisou/logs
Source Space:      [missing] /home/dennisou/src
DESTDIR:            [unused] None
--------------------------------------------------------------------------------
Devel Space Layout:          linked
Install Space Layout:        None
--------------------------------------------------------------------------------
Additional CMake Args:       -DPYTHON_EXECUTABLE=/home/zhangman/anaconda3/bin/python -DPYTHON_INCLUDE_DIR=/home/zhangman/anaconda3/include/python3.7m -DPYTHON_LIBRARY=/home/zhangman/anaconda3/lib/libpython3.7m.so -DCMAKE_BUILD_TYPE=Release-DSETUPTOOLS_DEB_LAYO
Additional Make Args:        None
Additional catkin Make Args: None
Internal Make Job Server:    True
Cache Job Environments:      False
--------------------------------------------------------------------------------
Buildlisted Packages:        None
Skiplisted Packages:         None
--------------------------------------------------------------------------------


--------------------------------------------------------------------------------
WARNING: Source space `/home/dennisou/src` does not yet exist.