@Test
public void getTaxAmount() {

    assertNull(new OcrResponseParser(null).getTaxAmount());
    assertNull(new OcrResponseParser(new OcrResponse(null, null, null, null, null, null, null, null)).getTaxAmount());
    assertNull(new OcrResponseParser(new OcrResponse(null, new OcrResponseField<>(null, null), null, null, new OcrResponseField<>(null, null), null, null, null)).getTaxAmount());
    assertEquals("3.04", new OcrResponseParser(new OcrResponse(null, new OcrResponseField<>(3.04, null), null, null, null, null, null, null)).getTaxAmount());
}