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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 refresh(self, force_cache=False):
 """ Perform a system refresh. :param force_cache: Force an update of the camera cache """

        if self.check_if_ok_to_update() or force_cache:
            for sync_name, sync_module in self.sync.items():
                _LOGGER.debug("Attempting refresh of sync %s", sync_name)
                sync_module.refresh(force_cache=force_cache)
            if not force_cache:
                # Prevents rapid clearing of motion detect property
                self.last_refresh = int(time.time())
            return True
        return False