public static @NotNull Collection<YAMLKeyValue> getTopLevelKeys(final YAMLFile file) {
    final YAMLValue topLevelValue = file.getDocuments().get(0).getTopLevelValue();
    if (topLevelValue instanceof YAMLMapping) {
      return ((YAMLMapping)topLevelValue).getKeyValues();
    }
    else {
      return Collections.emptyList();
    }
  }
public static @NotNull Collection<YAMLKeyValue> getTopLevelKeys(final YAMLFile file)