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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 default(self):
 """Return the default manifest schema version. Depending on the docker version, <= 1.9, used to push the image to the registry, v2 schema may not be available. In such case, the v1 schema should be used when interacting with the registry. An OCI digest will only be present when the manifest was pushed as an OCI digest. """

        return self.v2_list or self.oci_index or self.oci or self.v2 or self.v1