def association_custom(self, association_name, association_resource=None):
        """Custom Indicator association for this resource with resource value.

        **Example Endpoints URI's**

        +--------+--------------------------------------------------------------------------+
        | HTTP   | API Endpoint URI's                                                       |
        +========+==========================================================================+
        | {base} | /v2/indicators/{indicatorType}/{uniqueId}/associations/{associationName} |
        +--------+--------------------------------------------------------------------------+
        | GET    | {base}/indicators                                                        |
        +--------+--------------------------------------------------------------------------+
        | GET    | {base}/indicators/{indicatorType}                                        |
        +--------+--------------------------------------------------------------------------+
        | DELETE | {base}/indicators/{indicatorType}/{value}                                |
        +--------+--------------------------------------------------------------------------+
        | POST   | {base}/indicators/{indicatorType}/{value}                                |
        +--------+--------------------------------------------------------------------------+

        Args:
            association_name (string): The name of the custom association as defined in the UI.
            association_resource (object): An instance of Resource for an Indicator or sub type.
        """
        resource = self.copy()
        association_api_branch = self.tcex.indicator_associations_types_data.get(
            association_name, {}
        ).get('apiBranch')
        if association_api_branch is None:
            self.tcex.handle_error(305, [association_name])

        # handle URL difference between Custom Associations and File Actions
        custom_type = 'associations'
        file_action = self.tcex.utils.to_bool(
            self.tcex.indicator_associations_types_data.get(association_name, {}).get('fileAction')
        )
        if file_action:
            custom_type = 'actions'

        resource._request_entity = 'indicator'
        if association_resource is not None:
            resource._request_uri = '{}/{}/{}/{}'.format(
                resource._request_uri,
                custom_type,
                association_api_branch,
                association_resource.request_uri,
            )
        else:
            resource._request_uri = '{}/{}/{}/indicators'.format(
                resource._request_uri, custom_type, association_api_branch
            )
        return resource