code: func (b *Backend) PurgeGroupMeta(groupUUID string) error {
  	input := &dynamodb.DeleteItemInput{
  		Key: map[string]*dynamodb.AttributeValue{
  			"GroupUUID": {
  				N: aws.String(groupUUID),
  			},
  		},
  		TableName: aws.String(b.cnf.DynamoDB.GroupMetasTable),
  	}
  	_, err := b.client.DeleteItem(input)
  
  	if err != nil {
  		return err
  	}
  	return nil
  }
docs: // PurgeGroupMeta ...