It is an interpreter and that's absolutely correct. They could've even said "A vm in Python" because that is a VM, just without JIT etc. The compiler includes a parser usually, but interpreters in the purest sense of the word interpret the semantics of some structure corresponding to the code.
It's not an interpreter of the programming language Python, however. It's a VM for Python bytecode, which is not what most people understand as Python, right?
