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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 code(self, code):
 """ Sets the code of this ErrorResponse. Response code. :param code: The code of this ErrorResponse. :type: int """

        allowed_values = [400, 401, 404]
        if code not in allowed_values:
            raise ValueError(
                "Invalid value for `code` ({0}), must be one of {1}"
                .format(code, allowed_values)
            )

        self._code = code