code: def _send(self, sender, to, subject, message, cc=None, bcc=None, attach=None, replyto=None):
          
          self.mailer.send(sender, to, subject, plain=message, cc=cc, bcc=bcc, attach=attach, replyto=replyto)
          return
docs: Send a Letter (MESSAGE) from SENDER to TO, with the subject SUBJECT
  
          Arguments:
          - `sender`: unicode
          - `to`: unicode
          - `subject`: unicode
          - `message`: unicode
          - `cc`: str or [str]
          - `bcc`: str or [str]
          ` `replyto`: str
  
          Return: None
          Exceptions: None