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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
group module return values are undocumented.
<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
group
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.0
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/aschultz/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.3 (default, Apr 09 2019, 05:18:21) [GCC]
```
platform = 'Linux'
    distribution = 'Alpine'
def main():
    module = AnsibleModule(
        argument_spec=dict(
            state=dict(type='str', default='present', choices=['absent', 'present']),
            name=dict(type='str', required=True),
            gid=dict(type='int'),
            system=dict(type='bool', default=False),
            local=dict(type='bool', default=False),
            non_unique=dict(type='bool', default=False),
        ),
        supports_check_mode=True,
        required_if=[
            ['non_unique', True, ['gid']],
        ],
    )
    group = Group(module)
    module.debug('Group instantiated - platform %s' % group.platform)
    if group.distribution:
        module.debug('Group instantiated - distribution %s' % group.distribution)
    rc = None
    out = ''
    err = ''
    result = {}
    result['name'] = group.name
    result['state'] = group.state
    if group.state == 'absent':
        if group.group_exists():