'Close the connection and cause all outstanding L{request} L{Deferred}s
to fire with an error.'

def abort(self):

    if (self._state == 'CONNECTION_LOST'):
        return succeed(None)
    self.transport.loseConnection()
    self._state = 'ABORTING'
    d = Deferred()
    self._abortDeferreds.append(d)
    return d
