public TelegramMultipartBuilder addJsonPart(String fieldName, Object value) throws JsonProcessingException {
        if (value != null) {
            internalBuilder.addFormDataPart(fieldName, mapper.writeValueAsString(value));
        }
        return this;
    }
@Test
    public void testAddJsonPart() {
        try {
            Location location = new Location(1000d, 1000d);
            MultipartBody result = multipartBuilder.addJsonPart("TestPart", location).build();
            assertNotNull(result);
            assertEquals(1, result.size());
        } catch (Exception e) {
            fail(e);
        }
    }