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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:
 async def prodAllOnce(self):
 """ Call `prod` once for each Prodable in this Looper :return: the sum of the number of events executed successfully """

        # TODO: looks like limit is always None???
        limit = None
        s = 0
        for n in self.prodables:
            s += await n.prod(limit)
        return s