title: Python smtplib and multiple messages per connection
body: <p>recently i'm studing the smtplib smtp client library for python, but i could not find any reference to the PIPELINING protocol against smtp servers that support it.
  Is there something i'm missing? It's not yet implemented maybe? Any other implementations rather than smtplib with PIPELINING enabled?</p>
  
  <p>Thanks</p>