Error in Multi-uav SITL:How to solve "xacro.py: error: expected exactly one input file as argument"

Hello everyone.

I had followed the guide on multi-vehicle simulation: Multi-Vehicle Simulation · PX4 Developer Guide.

But I failed when I run the command that “roslaunch px4 multi_uav_mavros_sitl.launch”

And the output is the following:

Done checking log file disk usage. Usage is <1GB.
Usage: xacro.py [options]

xacro.py: error: expected exactly one input file as argument
while processing /home/burobotics/Guang/src/Firmware/launch/single_vehcile_spawn.launch:
Invalid tag: Cannot load command parameter [iris_1_sdf]: command [/opt/ros/kinetic/share/xacro/xacro.py /home/burobotics/Guang/src/Firmware/Tools/sitl_gazebo/models/rotors_description/urdf/iris_base.xacro rotors_description_dir:=/home/burobotics/Guang/src/Firmware/Tools/sitl_gazebo/models/rotors_description mavlink_udp_port:=14560 > iris_1.urdf ; ‘gz sdf -p iris_1.urdf’] returned with code [2].

Param xml is
The traceback for the exception was written to the log file

There exists a same issue in github, but the author closed the issue.