docs: public com.squareup.okhttp.Call getOpportunitiesGroupsGroupIdAsync(Integer groupId, String acceptLanguage,
              String datasource, String ifNoneMatch, String language,
              final ApiCallback<OpportunitiesGroupResponse> callback) throws ApiException {
  
          com.squareup.okhttp.Call call = getOpportunitiesGroupsGroupIdValidateBeforeCall(groupId, acceptLanguage,
                  datasource, ifNoneMatch, language, callback);
          Type localVarReturnType = new TypeToken<OpportunitiesGroupResponse>() {
          }.getType();
          apiClient.executeAsync(call, localVarReturnType, callback);
          return call;
      }