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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]
```
cmd = [self.module.get_bin_path('pw', True), 'groupadd', self.name]
        if self.gid is not None:
            cmd.append('-g')
            cmd.append(str(self.gid))
            if self.non_unique:
                cmd.append('-o')
        return self.execute_command(cmd)
    def group_mod(self, **kwargs):
        cmd = [self.module.get_bin_path('pw', True), 'groupmod', self.name]
        info = self.group_info()
        cmd_len = len(cmd)
        if self.gid is not None and int(self.gid) != info[2]:
            cmd.append('-g')
            cmd.append(str(self.gid))
            if self.non_unique:
                cmd.append('-o')
        
        if cmd_len != len(cmd):
            if self.module.check_mode:
                return (0, '', '')
            return self.execute_command(cmd)
        return (None, '', '')
class DragonFlyBsdGroup(FreeBsdGroup):
    """
    This is a DragonFlyBSD Group manipulation class.
    It inherits all behaviors from FreeBsdGroup class.
    """
    platform = 'DragonFly'
class DarwinGroup(Group):