To Manually Test:

Create a playbook in any directory: $ touch testmod.yml

Add the following to the new playbook file:

- name: test my new module
  connection: local
  hosts: localhost
  tasks:
  - name: run the new module
    my_new_test_module:
      name: 'hello'
      new: true
    register: testout
  - name: dump test output
    debug:
      msg: '{{ testout }}'

Run the playbook and analyze the output: $ ansible-playbook ./testmod.yml

To run pytest against a single test module, you can do the following (provide the path to the test module appropriately):

$ pytest -r a --cov=. --cov-report=html --fulltrace --color yes test/units/modules/.../test/my_new_test_module.py