docs: public static Field getField(Class clazz, String fieldName) {
          if (Map.class.isAssignableFrom(clazz)) {
              return new Field(new MapField(fieldName));
          }
          java.lang.reflect.Field field = null;
          while (field == null && clazz != null) {
              try {
                  field = clazz.getDeclaredField(fieldName);
                  field.setAccessible(true);
              } catch (Exception e) {
                  clazz = clazz.getSuperclass();
              }
          }
          return new Field(field);
      }