c# - EF 6 dependency on System.Data.Entity -

With EF6, I understand that all EF related classes have been moved to EntityFramework.dll. I see the following code that is using the DbContext class

  Namespace ConsoleApplication1 {using the system; Using System.Data.Entity; Using System.Data.Entity.Infrastructure; Public partial class MyDataModel: DbContext {Public MyDataModel (): Base ("name = MyDataModel") {} Safe Override Zero OnModelCreating {DbModelbuilder Modalbilder} {New UnintentionalCodeFirstException (); }  

This DbContext class is defined in System.Data.Entity, but in the context in the project, the section System.Data.Entity.dll has no reference. Two questions

1. Does this mean that EF still has system dependence? Data.Entity
2. Why the system has no context in this case. Data.Entity.dll In this case

system. Data. Definition is part of EF6 .