Launch python file in Roslaunch command

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Hi!

I need some help running a python script from a roslaunch command. I have a RPlidar connected to my raspberry pi which is ROS configured. I have a special software part of RViz called Hector Slam installed. Also connected to the raspberry pi is an actuator running a simple program.

When I type roslaunch hector_slam_launch tutorial.launch , I want a python file to activate which starts the actuator.

Simple Actuator Code:

from gpiozero import AngularServo
from time import sleep

servo = AngularServo(18, min_pulse_width=0.0006, max_pulse_width=0.0023)

while (True):
    servo.angle = 90
    sleep(2)
    servo.angle = 0
    sleep(2)
    servo.angle = -90
    sleep(2)

Now I have called this file servotest.py. I have placed it in the directory hector_slam_launch as well and I have used the command in terminal that makes it an executable (chmod +x servotest.py). In the terminal though if I do ./servotest it comes up with this error in terminal:

from: can't read /var/mail/gpiozero
from: can't read /var/mail/time
./servotest.py: line 3: $'\r': command not found
./servotest.py: line 4: syntax error near unexpected token `('
./servotest.py: line 4: `servo = AngularServo(18, min_pulse_width=0.0006, max_pu'se_width=0.0023)

This python file works perfectly when launching Thonny (python IDE) and clicking run.

I have also added in the tutorial.launch file lines 8 and 9 (the two lines beginning with <node> and </node>):

<?xml version="1.0"?>

<launch>

  <arg name="geotiff_map_file_path" default="$(find hector_geotiff)/maps"/>

  <param name="/use_sim_time" value="false"/>
  <node pkg="hector_slam_launch" type="servotest.py" name="servotest">
  </node>
  <node pkg="rviz" type="rviz" name="rviz"
    args="-d $(find hector_slam_launch)/rviz_cfg/mapping_demo.rviz"/>

  <include file="$(find hector_mapping)/launch/mapping_default.launch"/>

  <include file="$(find hector_geotiff_launch)/launch/geotiff_mapper.launch">
    <arg name="trajectory_source_frame_name" value="scanmatcher_frame"/>
    <arg name="map_file_path" value="$(arg geotiff_map_file_path)"/>
  </include>

</launch>

When in command prompt and I enter roslaunch hector_slam_launch tutorial.launch* , the Hector slam starts up In RViz along with all the necessary values in the command prompt but it also comes up with errors.