docs: def compose(self, to, subject, text):
          """Login required.  Sends POST to send a message to a user.  Returns True or raises :class:`exceptions.UnexpectedResponse` if non-"truthy" value in response.
          
          URL: ``http://www.reddit.com/api/compose/``
          
          :param to: username or :class`things.Account` of user to send to
          :param subject: subject of message
          :param text: message body text
          """
          if isinstance(to, Account):
              to = to.name
          data = dict(to=to, subject=subject, text=text)
          j = self.post('api', 'compose', data=data)
          return assert_truthy(j)