code: public boolean isModified() {
          for (String key : mStatus.keySet()) {
              FieldStatus status = getStatus(key);
              if (status == FieldStatus.DELETED || status == FieldStatus.MODIFIED) {
                  return true;
              }
          }
  
          return false;
      }
docs: Returns whether at least one field in the container has been modified
  
  @return true if at least the value of one field in the container has been modified, false
  otherwise