    func testMapToQuarterlyMobileDataUsages() {
        let testData1 = "{}"
        let result1 = DataMappingServices.getInstance().mapToQuarterlyMobileDataUsages(json: testData1)
        XCTAssertEqual(result1.count ,0, "MapToQuarterlyMobileDataUsages is wrong")
        let testData2 = "{\"success\": true, \"result\": {\"resource_id\": \"a807b7ab-6cad-4aa6-87d0-e283a7353a0f\", \"fields\": [{\"type\": \"int4\", \"id\": \"_id\"}, {\"type\": \"text\", \"id\": \"quarter\"}, {\"type\": \"numeric\", \"id\": \"volume_of_mobile_data\"}], \"records\": [{\"volume_of_mobile_data\": \"18.47368\", \"quarter\": \"2018-Q2\", \"_id\": 56}], \"offset\": 55, \"total\": 56}}"

        let result2 = DataMappingServices.getInstance().mapToQuarterlyMobileDataUsages(json: jsonSerialization(str: testData2))
        XCTAssert(result2.count == 1)
    }
    
    //todo