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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 update_if_client(fctn):
 """Intercept and check updates from server if bundle is in client mode."""

    @functools.wraps(fctn)
    def _update_if_client(self, *args, **kwargs):
        b = self._bundle
        if b is None or not hasattr(b, 'is_client'):
            return fctn(self, *args, **kwargs)
        elif b.is_client and \
                (b._last_client_update is None or
                (datetime.now() - b._last_client_update).seconds > 1):

            b.client_update()
        return fctn(self, *args, **kwargs)
    return _update_if_client