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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
On the following page: https://docs.ansible.com/ansible/latest/reference_appendices/config.html
In the first 'Note:' section there is the following text:
```
# some basic default values...
inventory = /etc/ansible/hosts  ; This points to the file that lists your hosts
```
When I paste only the above line in a new ~/.ansible.cfg file, I get the following warning message for the ansible ping command:
```
[host]> ansible all -m ping
[WARNING]: Unable to parse /etc/ansible/hosts  ; This points to the file that lists your
hosts as an inventory source
[WARNING]: No inventory was parsed, only implicit localhost is available
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit
localhost does not match 'all'
```

When I remove the comment text starting from ';' to the end of the line from the file '~/.ansible.cfg' and re-run the command, the above issue is resolved.

<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->
_Btw, the 'Edit on GitHub' in the above link takes me to a 404 Not Found 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 -->
docs.ansible.com website

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.10.6
<removed personally identifiable information from the output>
  python version = 3.8.2 (default, Dec 21 2020, 15:06:04) [Clang 12.0.0 (clang-1200.0.32.29)]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_HOST_LIST <this is the only line, but I've removed personally identifiable information here>
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. OS version, browser, etc. -->
Chrome browser

##### ADDITIONAL INFORMATION
<!--- Describe how this improves the documentation, e.g. before/after situation or screenshots -->

<!--- HINT: You can paste gist.github.com links for larger files -->

I'm a new user of ansible but I believe the comment guidance on the above-mentioned link is an error.

return value, origin
            
            try:
                value = ensure_type(value, defs[config].get('type'), origin=origin)
            except ValueError as e:
                if origin.startswith('env:') and value == '':
                    
                    origin = 'default'
                    value = ensure_type(defs[config].get('default'), defs[config].get('type'), origin=origin)
                else:
                    raise AnsibleOptionsError('Invalid type for configuration option %s: %s' %
                                              (to_native(_get_entry(plugin_type, plugin_name, config)), to_native(e)))
            
            if value is not None and 'choices' in defs[config] and defs[config]['choices'] is not None:
                if value not in defs[config]['choices']:
                    raise AnsibleOptionsError('Invalid value "%s" for configuration option "%s", valid values are: %s' %
                                              (value, to_native(_get_entry(plugin_type, plugin_name, config)), defs[config]['choices']))
            
            if 'deprecated' in defs[config] and origin != 'default':
                self.DEPRECATED.append((config, defs[config].get('deprecated')))
        else:
            raise AnsibleError('Requested entry (%s) was not defined in configuration.' % to_native(_get_entry(plugin_type, plugin_name, config)))
        return value, origin
    def initialize_plugin_configuration_definitions(self, plugin_type, name, defs):
        if plugin_type not in self._plugins:
            self._plugins[plugin_type] = {}
        self._plugins[plugin_type][name] = defs
    def update_config_data(self, defs=None, configfile=None):
        ''' really: update constants '''
        if defs is None: