I agree that mostly hashes do their job. The same time I think there is some corner cases. As nature of the python packages can be a bit different comparing to

I agree that mostly hashes do their job. The same time I think there is some corner cases. As nature of the python packages can be a bit different comparing to the other packaging systems. File setup.py actually is python file and it is executed when processes. So, it possible that depending on existence of some libraries on your system you will get very different results. For example packages can require very different dependency if you build on Windows or Linux. This case hashes can't do much to guaranty consistency.