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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 frequencies_iter(self):
 """ Iterates over all non-zero frequencies of logical conjunction mappings in this list Yields ------ tuple[caspo.core.mapping.Mapping, float] The next pair (mapping,frequency) """

        f = self.__matrix.mean(axis=0)
        for i, m in self.mappings.iteritems():
            yield m, f[i]