docs: def check_attribute_mapping_exists(resource_attr_id_source, resource_attr_id_target, **kwargs):
      """
          Check whether an attribute mapping exists between a source and target resource attribute.
          returns 'Y' if a mapping exists. Returns 'N' in all other cases.
      """
      qry = db.DBSession.query(ResourceAttrMap).filter(
                  ResourceAttrMap.resource_attr_id_a == resource_attr_id_source,
                  ResourceAttrMap.resource_attr_id_b == resource_attr_id_target).all()
  
      if len(qry) > 0:
          return 'Y'
      else:
          return 'N'