def METHOD_NAME(self, item, identity_field=None):
    # email not available for gitter
    identity = {
        'username': None,
        'name': None,
        'email': None
    }
    author = item['data'][self.get_field_author()] \
        if self.get_field_author() in item['data'] else None
    if not author:
        return identity
    identity['username'] = author.get('username', None)
    identity['name'] = author.get('full_name', None)
    identity['email'] = author.get('email', None)
    return identity