title: Read from bytes not filename to convert audio
body: <p>I have small-sized sound files stored in <code>MongoDB</code> as <code>BSON</code>. 
  Task is to retrieve Binary data from the database, convert it to an appropriate format and send back to the front end. 
  The problem is with the converting. I have found <code>pydub</code> can be used for this. </p>
  
  <p>My code is as follows</p>
  
  <pre><code> query_param = json_data['retriever']
   query_param1 = query_param.replace('"', "");
   data = db.soundData
   y = data.find_one({'name': query_param1})
   s = y['data'] // here I retrieve the binary data 
   AudioSegment.from_file(s).export(x, format="mp3")
   return send_file(x, 'audio/mp3')
  </code></pre>
  
  <p>The question is with Audiosegment line as it does not follow the standard of 
  <code>AudioSegment.from_wav("/input/file.wav").export("/output/file.mp3", format="mp3")</code>
  and an error of <code>'bytes' object has no attribute 'read'</code> is still thrown. Is it achievable with <code>pydub</code>? </p>