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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 -->

NAME = "hcloud"
    def _configure_hcloud_client(self):
        self.api_token = self.get_option("token")
        if self.api_token is None:
            raise AnsibleError(
                "Please specify a token, via the option token or via environment variable HCLOUD_TOKEN")
        self.endpoint = os.getenv("HCLOUD_ENDPOINT") or "https://api.hetzner.cloud/v1"
        self.client = hcloud.Client(token=self.api_token,
                                    api_endpoint=self.endpoint,
                                    application_name="ansible-inventory",
                                    application_version=__version__)
    def _test_hcloud_token(self):
        try:
            
            
            self.client.locations.get_all()
        except hcloud.APIException:
            raise AnsibleError("Invalid Hetzner Cloud API Token.")
    def _get_servers(self):
        if len(self.get_option("label_selector")) > 0:
            self.servers = self.client.servers.get_all(label_selector=self.get_option("label_selector"))
        else:
            self.servers = self.client.servers.get_all()
    def _filter_servers(self):