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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 make_result(self):
 """Construct the result dict to be preserved in the build metadata."""

        result = {}
        if self._base_image_build:
            result[BASE_IMAGE_KOJI_BUILD] = self._base_image_build
        if self._parent_builds:
            result[PARENT_IMAGES_KOJI_BUILDS] = self._parent_builds
        return result if result else None