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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 evaluate(self, verbose=False, decode=True, passes=None, num_threads=1, apply_experimental_transforms=True):
 """Evaluate the stored expression. Parameters verbose : bool, optional Whether to print output for each Weld compilation step. decode : bool, optional Whether to decode the result passes : list, optional Which Weld optimization passes to apply num_threads : int, optional On how many threads to run Weld apply_experimental_transforms : bool Whether to apply the experimental Weld transforms. Returns ------- numpy.ndarray Output of the evaluated expression. """

        if isinstance(self.weld_expr, WeldObject):
            old_context = dict(self.weld_expr.context)

            for key in self.weld_expr.context.keys():
                if LazyResult._cache.contains(key):
                    self.weld_expr.context[key] = LazyResult._cache.get(key)

            evaluated = self.weld_expr.evaluate(to_weld_vec(self.weld_type,
                                                            self.ndim),
                                                verbose,
                                                decode,
                                                passes,
                                                num_threads,
                                                apply_experimental_transforms)

            self.weld_expr.context = old_context

            return evaluated
        else:
            return self.weld_expr