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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 disconnect(self):
 """Disconnect from the card."""


        # when __del__() is invoked in response to a module being deleted,
        # e.g., when execution of the program is done, other globals referenced
        # by the __del__() method may already have been deleted.
        # this causes CardConnection.disconnect to except with a TypeError
        try:
            CardConnection.disconnect(self)
        except TypeError:
            pass
        if None != self.hcard:
            hresult = SCardDisconnect(self.hcard, self.disposition)
            if hresult != 0:
                raise CardConnectionException(
                    'Failed to disconnect: ' + \
                    SCardGetErrorMessage(hresult))
            self.hcard = None