code: public BoxRetentionPolicyAssignment.Info assignToMetadataTemplate(String templateID,
                                                                        MetadataFieldFilter... fieldFilters) {
          return BoxRetentionPolicyAssignment.createAssignmentToMetadata(this.getAPI(), this.getID(), templateID,
                  fieldFilters);
      }
docs: Assigns this retention policy to a metadata template, optionally with certain field values.
  @param templateID the ID of the metadata template to apply to.
  @param fieldFilters optional field value filters.
  @return info about the created assignment.