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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 random_leaf(self):
        "Returns a random variable with the associated weight"
        for i in range(self._number_tries_feasible_ind):
            var = np.random.randint(self.nvar)
            v = self._random_leaf(var)
            if v is None:
                continue
            return v
        raise RuntimeError("Could not find a suitable random leaf")