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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 eval_to_ast(self, e, n, extra_constraints=(), exact=None):
 """ Evaluates expression e, returning the results in the form of concrete ASTs. """

        return [ ast.bv.BVV(v, e.size()) for v in self.eval(e, n, extra_constraints=extra_constraints, exact=exact) ]