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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 _binop_handler(nodetype):
 """ Factory function for binary operator handlers. """

    def _handler(toplevel, stack_builders):
        right = make_expr(stack_builders)
        left = make_expr(stack_builders)
        return ast.BinOp(left=left, op=nodetype(), right=right)
    return _handler