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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 -->

from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
DOCUMENTATION = r"""
    name: hcloud
    plugin_type: inventory
    author:
      - Lukas Kaemmerling (@lkaemmerling)
    short_description: Ansible dynamic inventory plugin for the Hetzner Cloud.
    version_added: "2.8"
    requirements:
        - python >= 2.7
        - hcloud-python >= 1.0.0
    description:
        - Reads inventories from the Hetzner Cloud API.
        - Uses a YAML configuration file that ends with hcloud.(yml|yaml).
    extends_documentation_fragment:
        - constructed
    options:
        plugin:
            description: marks this as an instance of the "hcloud" plugin
            required: true
            choices: ["hcloud"]
        token:
            description: The Hetzner Cloud API Token.
            required: true
            env:
                - name: HCLOUD_TOKEN
        connect_with: