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##### SUMMARY
@LKaemmerling As discussed in https://github.com/ansible/ansible/issues/59133#issuecomment-515133800, you said there would be network filtering in the hcloud dynamic inventory plugin (https://docs.ansible.com/ansible/latest/plugins/inventory/hcloud.html) in Ansible 2.9. But this functionality still doesn't appear. Could it be added? There are many cases where you only want to run ansible commands against servers in some networks only.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
hcloud dynamic inventory


<!--- Describe how the feature would be used, why it is needed and what it would solve -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml

```

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

"""Return the possibly of a file being consumable by this plugin."""
        return (
            super(InventoryModule, self).verify_file(path) and
            path.endswith((self.NAME + ".yaml", self.NAME + ".yml"))
        )
    def parse(self, inventory, loader, path, cache=True):
        super(InventoryModule, self).parse(inventory, loader, path, cache)
        self._read_config_data(path)
        self._configure_hcloud_client()
        self._test_hcloud_token()
        self._get_servers()
        self._filter_servers()
        
        self.inventory.add_group(group="hcloud")
        for server in self.servers:
            self.inventory.add_host(server.name, group="hcloud")
            self._set_server_attributes(server)
            
            strict = self.get_option('strict')
            
            self._set_composite_vars(self.get_option('compose'), self.inventory.get_host(server.name).get_vars(), server.name, strict=strict)
            
            self._add_host_to_composed_groups(self.get_option('groups'), {}, server.name, strict=strict)
            
            self._add_host_to_keyed_groups(self.get_option('keyed_groups'), {}, server.name, strict=strict)