def populate_all_metadata():
for Metadata in list(registry.values()):<EOL><INDENT>InstanceMetadata = Metadata._meta.get_model('<STR_LIT>')<EOL>if InstanceMetadata is not None:<EOL><INDENT>for model in Metadata._meta.seo_models:<EOL><INDENT>populate_metadata(model, InstanceMetadata)<EOL><DEDENT><DEDENT><DEDENT>
Create metadata instances for all models in seo_models if empty.
        Once you have created a single metadata instance, this will not run.
        This is because it is a potentially slow operation that need only be
        done once. If you want to ensure that everything is populated, run the
        populate_metadata management command.