I got the imports working by adding these two lines to the pubspec.yaml file:
cupertino_icons: ^0.1.3 flutter_gallery: ^2.4.0+20400
The first line is actually replacing the original cupertino-icons dependency that is version 1.0.0 and the flutter gallery dependency requires a different version, that is 0.1.3.
Then update the imports with ‘flutter pub get’
This site here lists all of the possible flutter_gallery imports.
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