code: def read_stb(library, session):
      
      status = ViUInt16()
      ret = library.viReadSTB(session, byref(status))
      return status.value, ret
docs: Reads a status byte of the service request.
  
      Corresponds to viReadSTB function of the VISA library.
  
      :param library: the visa library wrapped by ctypes.
      :param session: Unique logical identifier to a session.
      :return: Service request status byte, return value of the library call.
      :rtype: int, :class:`pyvisa.constants.StatusCode`