Ansible playbook error installing Plone 4.3.19 (setuptools version conflict) [SOLVED]

I'm using the playbook to set up Plone 4.3.19

ansible-playbook -K -i inventory.cfg playbook.yml

and am stuck with this error:

# sudo -u plone_buildout bin/buildout -c live.cfg
  Loading extensions.
Error: There is a version conflict.
We already have: setuptools 26.1.1

This is because versions.cfg contains setuptools = 7.0

How can I get past this? Commenting out that line doesn't work because the playbook (sensibly) refreshes the file.

Ah, maybe this from the ansible.plone_server playbook:

### plone_download_requirements_txt

    plone_download_requirements_txt: yes

Should we download a requirements.txt file from for the matching version of Plone?
If you set this to `no`, or if does not have a requirements file for the target version, we'll create one from a template.
If we create from template, the following settings are used, all of which may be overriden:

    plone_setuptools_version: '26.1.1'
    plone_zc_buildout_version: '2.5.3'
    plone_pip_version: '10.0.1'

Yup, that was it. I added these lines to my playbook.yml:

plone_download_requirements_txt: no
plone_setuptools_version: '7.0'
plone_zc_buildout_version: '1.7.1'
plone_pip_version: '9.0.1'

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