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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]
```
"""
    This is a Mac macOS Darwin Group manipulation class.
    This overrides the following methods from the generic class:-
      - group_del()
      - group_add()
      - group_mod()
    group manipulation are done using dseditgroup(1).
    """
    platform = 'Darwin'
    distribution = None
    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('dseditgroup', True)]
        cmd += ['-o', 'create']
        if self.gid is not None:
            cmd += ['-i', str(self.gid)]
        elif 'system' in kwargs and kwargs['system'] is True:
            gid = self.get_lowest_available_system_gid()
            if gid is not False:
                self.gid = str(gid)
                cmd += ['-i', str(self.gid)]
        cmd += ['-L', self.name]
        (rc, out, err) = self.execute_command(cmd)
        return (rc, out, err)
    def group_del(self):
        cmd = [self.module.get_bin_path('dseditgroup', True)]
        cmd += ['-o', 'delete']
        cmd += ['-L', self.name]
        (rc, out, err) = self.execute_command(cmd)
        return (rc, out, err)
    def group_mod(self, gid=None):