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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 mutualReceptions(self, idA, idB):
 """ Returns all pairs of dignities in mutual reception. """

        AB = self.receives(idA, idB)
        BA = self.receives(idB, idA)
        # Returns a product of both lists
        return [(a,b) for a in AB for b in BA]