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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 build_type(self, build_type):
 """ Sets the build_type of this BuildConfigurationRest. :param build_type: The build_type of this BuildConfigurationRest. :type: str """

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

        self._build_type = build_type