drawtext causes a muted video output

I am using both CLI ffmpeg and python-ffmpeg in the same environment, which is Termux app installed in a Samsung GS8+ Android phone. When I run this command I get the expected output (text overlayed on the input video). `$ ffmpeg -i input.mp4 -vf "drawtext=text='© Leóñardo da Vinci':x=(1100-text_w):y=(600-text_h):fontsize=32:fontcolor=black:box=1:boxcolor=white@0.5: boxborderw=5" -c:a copy ffmpeg_drawtext-output.mp4` When I run it in Python, the output video is muted (no audio): ``` ffmpeg \ .input("input.mp4") \ .drawtext(text='© Leónardo da Vinci', x='(1100-text_w)', y='(600-text_h)', fontsize=32, fontcolor='black', box=1, boxcolor='white@0.5', boxborderw=5) \ .output("pyffmpeg_out.mp4") \ .run() ``` Perhaps both commands are not equivalent? What is the exact `python-ffmpeg` implementation of the above `ffmpeg` command?