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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 addreadergroup(self, newgroup):
 """Add a reader group"""


        hresult, hcontext = SCardEstablishContext(SCARD_SCOPE_USER)
        if 0 != hresult:
            raise error(
                'Failed to establish context: ' + \
                SCardGetErrorMessage(hresult))
        try:
            hresult = SCardIntroduceReaderGroup(hcontext, newgroup)
            if 0 != hresult:
                raise error(
                    'Unable to introduce reader group: ' + \
                    SCardGetErrorMessage(hresult))
            else:
                innerreadergroups.addreadergroup(self, newgroup)

        finally:
            hresult = SCardReleaseContext(hcontext)
            if 0 != hresult:
                raise error(
                    'Failed to release context: ' + \
                    SCardGetErrorMessage(hresult))