code: func FromDescriptorsWithMediaType(descriptors []ManifestDescriptor, mediaType string) (*DeserializedManifestList, error) {
  	m := ManifestList{
  		Versioned: manifest.Versioned{
  			SchemaVersion: 2,
  			MediaType:     mediaType,
  		},
  	}
  
  	m.Manifests = make([]ManifestDescriptor, len(descriptors))
  	copy(m.Manifests, descriptors)
  
  	deserialized := DeserializedManifestList{
  		ManifestList: m,
  	}
  
  	var err error
  	deserialized.canonical, err = json.MarshalIndent(&m, "", "   ")
  	return &deserialized, err
  }
docs: // FromDescriptorsWithMediaType is for testing purposes, it's useful to be able to specify the media type explicitly