The install by xcode of a python3 binary in `/usr/bin` does not come with its own copy of pip3.
So either your command will fail to install or it will use a version of pip that is on PATH but was installed by some other version of python. So in either case you can't install a library into what you are mistakenly calling a system python.
So the original assertion was not true and you have not been able to make up an ex post justification for it.
So either your command will fail to install or it will use a version of pip that is on PATH but was installed by some other version of python. So in either case you can't install a library into what you are mistakenly calling a system python.
So the original assertion was not true and you have not been able to make up an ex post justification for it.