Convert an annotation file to a namespace file.

def convert_to_namespace(file, output, keyword):
    """Convert an annotation file to a namespace file."""
    resource = parse_bel_resource(file)
    write_namespace(
        namespace_keyword=(keyword or resource['AnnotationDefinition']['Keyword']),
        namespace_name=resource['AnnotationDefinition']['Keyword'],
        namespace_description=resource['AnnotationDefinition']['DescriptionString'],
        author_name='Charles Tapley Hoyt',
        namespace_domain=NAMESPACE_DOMAIN_OTHER,
        values=resource['Values'],
        citation_name=resource['Citation']['NameString'],
        file=output
    )