code: def start_tls(self, ssl_context: Union[bool, dict, ssl.SSLContext]=True) \
              -> 'SSLConnection':
          '''Start client TLS on this connection and return SSLConnection.
  
          Coroutine
          '''
          sock = self.writer.get_extra_info('socket')
          ssl_conn = SSLConnection(
              self._address,
              ssl_context=ssl_context,
              hostname=self._hostname, timeout=self._timeout,
              connect_timeout=self._connect_timeout, bind_host=self._bind_host,
              bandwidth_limiter=self._bandwidth_limiter, sock=sock
          )
  
          yield from ssl_conn.connect()
  
          return ssl_conf start_tls(self, ssl_context: Union[bool, dict, ssl.SSLContext]=True) \
              -> 'SSLConnection':
          '''Start client TLS on this connection and return SSLConnection.
  
          Coroutine
          '''
          sock = self.writer.get_extra_info('socket')
          ssl_conn = SSLConnection(
              self._address,
              ssl_context=ssl_context,
              hostname=self._hostname, timeout=self._timeout,
              connect_timeout=self._connect_timeout, bind_host=self._bind_host,
              bandwidth_limiter=self._bandwidth_limiter, sock=sock
          )
  
          yield from ssl_conn.connect()
  
          return ssl_conn
docs: Start client TLS on this connection and return SSLConnection.
  
          Coroutine