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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 get_digests(self):
 """ Returns a map of repositories to digests """


        digests = {}  # repository -> digest
        for registry in self.workflow.push_conf.docker_registries:
            for image in self.workflow.tag_conf.images:
                image_str = image.to_str()
                if image_str in registry.digests:
                    digest = registry.digests[image_str]
                    digests[image.to_str(registry=False)] = digest

        return digests