if ('hasOne' in model.relations && !utils.isObject(model.relations.hasOne)) {
        throw new errors.IllegalArgumentError(errorPrefix + modelName + '.relations.hasOne: Must be an object!', { actual: typeof model.relations.hasOne, expected: 'object' });
      } else if ('belongsTo' in model.relations && !utils.isObject(model.relations.belongsTo)) {
        throw new errors.IllegalArgumentError(errorPrefix + modelName + '.relations.belongsTo: Must be an object!', { actual: typeof model.relations.belongsTo, expected: 'object' });
      } else if ('hasMany' in model.relations && !utils.isObject(model.relations.hasMany)) {