FFMPEG Multi Audio Track Videos

#!/bin/bash

echo "An example of creating an Multi Audio Track Video."
echo "This can be used for different Languages or "
echo "============================================"
echo "             Getting Media                  "
echo "============================================"

#downloading Video and Audio tracks
youtube-dl -c "https://youtu.be/9L-chI5kj3A" -o video
youtube-dl -c -x --audio-format mp3 "https://youtu.be/1U7f5sczZ-c" -o track1.mp3

echo "Combining Both Audio Tracking into one Video file"
ffmpeg -i video* -i track1.mp3 -map 0 -map 1 -c copy output1.mkv

echo "Swapping Audio Tracks..."
ffmpeg -i output1.mkv -map 0:2 -map 0:1 -map 0:0 -c copy output2.mkv