ErrorSummary('No MediaQuery widget ancestor found.'),에러가 뜹니다..

bool debugCheckHasMediaQuery(BuildContext context) {
  assert(() {
    if (context.widget is! MediaQuery && context.getElementForInheritedWidgetOfExactType<MediaQuery>() == null) {
      throw FlutterError.fromParts(<DiagnosticsNode>[
        ErrorSummary('No MediaQuery widget ancestor found.'),
        ErrorDescription('${context.widget.runtimeType} widgets require a MediaQuery widget ancestor.'),
        context.describeWidget('The specific widget that could not find a MediaQuery ancestor was'),
        context.describeOwnershipChain('The ownership chain for the affected widget is'),
        ErrorHint(
          'No MediaQuery ancestor could be found starting from the context '
          'that was passed to MediaQuery.of(). This can happen because you '
          'have not added a WidgetsApp, CupertinoApp, or MaterialApp widget '
          '(those widgets introduce a MediaQuery), or it can happen if the '
          'context you use comes from a widget above those widgets.',
        ),
      ]);
    }

githubs 파일만 가져와서 실행했는데 error가 나오네요..