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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 unlock(self):
 """ Unlock the candidate config. Purpose: Unlocks the candidate configuration, so that other people can | edit the device. Requires the _session private variable to be | a type of a ncclient.manager.Manager. """

        if isinstance(self._session, manager.Manager):
            self._session.unlock()