在flutter应用程序中解析块映射错误时需要一个键

Question

当我在 pubspec.yaml 文件夹中添加以下行时：firebase_core: "0.7.0"

我收到以下消息：

Error on line 33, column 3: Expected a key while parsing a block mapping.
   ╷
33 │   cupertino_icons: ^0.1.3
   │   ^

代码片段：

   version: 1.0.0+1
    
    environment:
      sdk: ">=2.7.0 <3.0.0"
    
    dependencies:
     flutter:
      sdk: flutter
     firebase_core: "0.7.0"
    
    
       # The following adds the Cupertino Icons font to your application.
      # Use with the CupertinoIcons class for iOS style icons.
      cupertino_icons: ^0.1.3
      audioplayers: ^0.15.1

知道如何解决这个问题吗？