title: Error receiving mail with python 3 "sequence item 0: expected str instance, bytes found"
body: <p>I'm trying to receive emails on python with poplib, when I run the code I keep getting the following output <code>sequence item 0: expected str instance, bytes found</code>. Here is the whole code, if anyone knows a much simpler way of printing the receiving mail, I would appreciate if you could comment it. I would also like to be able to print only the emails of an determinate email. Thankyou.</p>
  
  <pre><code>import poplib
  from email import parser
  pop_conn = poplib.POP3_SSL('pop.gmail.com')
  pop_conn.user('mail@gmail.com')
  pop_conn.pass_('password')
  
  messages = [pop_conn.retr(i) for i in range(1, len(pop_conn.list()[1]) + 1)]
  # Concat message pieces:
  messages = ["\n".join(mssg[1]) for mssg in messages]
  #Parse message intom an email object:
  messages = [parser.Parser().parsestr(mssg) for mssg in messages]
  print(message.keys())
  for message in messages:
      print(message['subject'])
      print(message.get_payload())
  pop_conn.quit()
  </code></pre>