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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 _expr2code(self, arg_list, expr):
 """Convert the given symbolic expression into code."""

        code = lambdastr(arg_list, expr)
        function_code = code.split(':')[1].strip()
        #for arg in arg_list:
        #    function_code = function_code.replace(arg.name, 'self.'+arg.name)

        return function_code