Add reader to a reader group.

def addtoreadergroup(self, groupname):
        """Add reader to a reader group."""

        hresult, hcontext = SCardEstablishContext(SCARD_SCOPE_USER)
        if 0 != hresult:
            raise EstablishContextException(hresult)
        try:
            hresult = SCardIntroduceReader(hcontext, self.name, self.name)
            if 0 != hresult and SCARD_E_DUPLICATE_READER != hresult:
                raise IntroduceReaderException(hresult, self.name)
            hresult = SCardAddReaderToGroup(hcontext, self.name, groupname)
            if 0 != hresult:
                raise AddReaderToGroupException(hresult, self.name, groupname)
        finally:
            hresult = SCardReleaseContext(hcontext)
            if 0 != hresult:
                raise ReleaseContextException(hresult)