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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 someoneKnownSeen(self, home=None, camera=None):
 """ Return True if someone known has been seen """

        try:
            cam_id = self.cameraByName(camera=camera, home=home)['id']
        except TypeError:
            logger.warning("personSeenByCamera: Camera name or home is unknown")
            return False
        #Check in the last event is someone known has been seen
        if self.lastEvent[cam_id]['type'] == 'person':
            if self.lastEvent[cam_id]['person_id'] in self._knownPersons():
                return True
        return False