@staticmethod
def _get_firstname(optional, k2v):
    """Get first name to be used as the display name."""
    if 'geneName' in optional:
        return optional['geneName'][0]
    if 'name' in optional:
        names = optional['name']
        name = names[0] if k2v['databaseName'][:9] != 'KEGG Gene' else names[-1
            ]
        return name if k2v['identifier'] != name else ''
    return ''
