code: private Iterable<BoxRetentionPolicyAssignment.Info> getAssignments(String type, int limit, String ... fields) {
          QueryStringBuilder queryString = new QueryStringBuilder();
          if (type != null) {
              queryString.appendParam("type", type);
          }
          if (fields.length > 0) {
              queryString.appendParam("fields", fields);
          }
          URL url = ASSIGNMENTS_URL_TEMPLATE.buildWithQuery(getAPI().getBaseURL(), queryString.toString(), getID());
          return new BoxResourceIterable<BoxRetentionPolicyAssignment.Info>(getAPI(), url, limit) {
  
              @Override
              protected BoxRetentionPolicyAssignment.Info factory(JsonObject jsonObject) {
                  BoxRetentionPolicyAssignment assignment
                      = new BoxRetentionPolicyAssignment(getAPI(), jsonObject.get("id").asString());
                  return assignment.new Info(jsonObject);
              }
  
          };
      }
docs: Returns iterable with all assignments of given type of this retention policy.
  @param type the type of the retention policy assignment to retrieve. Can either be "folder" or "enterprise".
  @param limit the limit of entries per response. The default value is 100.
  @param fields the fields to retrieve.
  @return an iterable containing all assignments of given type.