How to change audio file bitrate (bits per second) in iOS Swift?

I need to write App in swift that records audio from mice and listen it, then lets user pick bitrate(bits per second) like(320 kbps, 256 kbps, 120 kbps) and listen again. The propose is that get recognizable audio in lower bitrate( if bitrate low, then the file is also small). Can you guys show me, or tell me where and how i can change bitrate of audio file in swift?

How to change audio file bitrate (bits per second) in iOS Swift?
 
 
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