molecule_yml - how is this variable populated?

[anudeepmk]

I couldn't find information regarding the molecule_yml , I am in the process of using delegated driver for using molecule for my existing instances (not provisioning and tearing them down )but just like converge and test on them!
I stumbled on this delegated_issue
I am trying to understand where is molecule_yml coming from and also any information on the docs?

     - name: Create molecule instance(s)
        vmware_guest:
          hostname: "{{ molecule_yml.driver.hostname }}"
          esxi_hostname: "{{ molecule_yml.driver.esxi_hostname }}"
          username: "{{ molecule_yml.driver.username }}"
          password: "{{ molecule_yml.driver.password }}"
          datacenter: "{{ molecule_yml.driver.datacenter }}"
          validate_certs: "{{ molecule_yml.driver.validate_certs }}"
          resource_pool: "{{ molecule_yml.driver.resource_pool }}"
          folder: "{{ molecule_yml.driver.folder }}"

I cloned the repo on my local and found this below(grep'ing for molecule_yml)

./molecule/provisioner/ansible.py:                    "molecule_yml": "{{ lookup('file', molecule_file) | molecule_from_yaml }}",
./molecule/provisioner/ansible.py:                    "molecule_yml.provisioner.log|default(False) | bool }}",

please advise on this
@retr0h

[corserp]

Thanks