Type or namespace Api does not exist in 'Google'

I did as instructed by im getting this error here, but, when compiling the solution I get the erro `Error: The type or namespace name 'Api' does not exist in the namespace 'Google' (are you missing an assembly reference?)`

any ideia of what im doing wrong?!?


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* ID: 25375ca1-0ce8-a3ca-0c3a-446328f09ba1
* Version Independent ID: 25375ca1-0ce8-a3ca-0c3a-446328f09ba1
* Content: [gRPC JSON transcoding in ASP.NET Core gRPC apps](https://learn.microsoft.com/en-us/aspnet/core/grpc/json-transcoding?view=aspnetcore-7.0)
* Content Source: [aspnetcore/grpc/json-transcoding.md](https://github.com/dotnet/AspNetCore.Docs/blob/main/aspnetcore/grpc/json-transcoding.md)
* Product: **aspnet-core**
* Technology: **aspnetcore-grpc**
* GitHub Login: @JamesNK
* Microsoft Alias: **jamesnk**