+
                    duration: const Duration(seconds: 3),

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+
                    opacity: opacity,

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child: Column(

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children: const [

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Text('Type: Owl'),

3. Set the duration of the animation

In addition to an opacity parameter, AnimatedOpacity requires a
duration to use for its animation. For this example,
you can start with 2 seconds:

{opacity3 → opacity4}/lib/main.dart

@@ -28,7 +28,7 @@

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28

),

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onPressed: () => {}),

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