code: def do_handshake(self):
          
          if self._error:
              raise compat.saved_exc(self._error)
          elif self._closing or self._handle.closed:
              raise TransportError('SSL transport is closing/closed')
          self._write_backlog.append([b'', True])
          self._process_write_backlog()
docs: Start the SSL handshake.
  
          This method only needs to be called if this transport was created with
          *do_handshake_on_connect* set to False (the default is True).
  
          The handshake needs to be synchronized between the both endpoints, so
          that SSL record level data is not incidentially interpreted as
          plaintext. Usually this is done by starting the handshake directly
          after a connection is established, but you can also use an application
          level protocol.