How to mock behavior of AutoMapper Mapping in Nsubstitute

Question

Currently I have something like this :-

    var someclass1 = JsonConvert.Deserialize<SomeClass1>(RandomData);
    var someclass2 = AutoMapper.Mapper.Map<Models.SomeClass2.SomeClass2>(someclass1);

    Assert.Equal(someclass2.Count, 1);

I know in order to do this I need to create a mock for IMappingEngine, but how do I mock the mapping above ?