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for /f "tokens=1 delims=." %a in ('dir /b *.wma C:\directory\audio_files') do ffmpeg -i C:\directory\audio_files\%a.wma -acodec aac C:\directory\audio_files\%a.mp3
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for /f "tokens=1 delims=." %a in ('dir /b *.wma C:\directory\audio_files') do ffmpeg -i C:\directory\audio_files\%a.wma -acodec aac C:\directory\audio_files\%a.mp3
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