Generate the metadata to send the napp package.

def create_metadata(*args, **kwargs):  # pylint: disable=unused-argument
        """Generate the metadata to send the napp package."""
        json_filename = kwargs.get('json_filename', 'kytos.json')
        readme_filename = kwargs.get('readme_filename', 'README.rst')
        ignore_json = kwargs.get('ignore_json', False)
        metadata = {}

        if not ignore_json:
            try:
                with open(json_filename) as json_file:
                    metadata = json.load(json_file)
            except FileNotFoundError:
                print("ERROR: Could not access kytos.json file.")
                sys.exit(1)

        try:
            with open(readme_filename) as readme_file:
                metadata['readme'] = readme_file.read()
        except FileNotFoundError:
            metadata['readme'] = ''

        try:
            yaml = YAML(typ='safe')
            openapi_dict = yaml.load(Path('openapi.yml').open())
            openapi = json.dumps(openapi_dict)
        except FileNotFoundError:
            openapi = ''
        metadata['OpenAPI_Spec'] = openapi

        return metadata