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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def read_stb(library, session):
 """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` """

    status = ViUInt16()
    ret = library.viReadSTB(session, byref(status))
    return status.value, ret