["python","pip","pypi"]
pip requirements.txt with alternative index

I want to put all the requirements of a repoze Zope2 install in a pip requirements file. Most of the repoze packages don't seem to be on PyPi, but there's an alternative PyPi index for them here. But I can't figure out how to tell pip to use that index together with a requirements file. For single packages, it's easy pip install zopelib -i http://dist.repoze.org/zope2/2.10/simple/ I tried the following pip install -r requirements.txt -i http://dist.repoze.org/zope2/2.10/simple/ or in my requirements.txt all kind or permutations of these: zopelib -i http://dist.repoze.org/zope2/2.10/simple/ zopelib --index http://dist.repoze.org/zope2/2.10/simple/ -i http://dist.repoze.org/zope2/2.10/simple/ zopelib or (because the documentation says "Note that all these options must be on a line of their own.") --index http://dist.repoze.org/zope2/2.10/simple/ zopelib So, what's the correct way of telling pip to use http://dist.repoze.org/zope2/2.10/simple/ as index?
requirements.txt: -i http://dist.repoze.org/zope2/2.10/simple zopelib Example: $ pip install -r requirements.txt ... Successfully installed zopelib Note that -i takes effect for the entire requirements file. If you want to use different indexes, you can have multiple requirements files. https://pip.pypa.io/en/stable/reference/requirements-file-format/#supported-options