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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 -->

if self.get_option("locations"):
            tmp = []
            for server in self.servers:
                if server.datacenter.location.name in self.get_option("locations"):
                    tmp.append(server)
            self.servers = tmp
        if self.get_option("types"):
            tmp = []
            for server in self.servers:
                if server.server_type.name in self.get_option("types"):
                    tmp.append(server)
            self.servers = tmp
        if self.get_option("images"):
            tmp = []
            for server in self.servers:
                if server.image is not None and server.image.os_flavor in self.get_option("images"):
                    tmp.append(server)
            self.servers = tmp
    def _set_server_attributes(self, server):
        self.inventory.set_variable(server.name, "id", to_native(server.id))
        self.inventory.set_variable(server.name, "name", to_native(server.name))
        self.inventory.set_variable(server.name, "status", to_native(server.status))
        self.inventory.set_variable(server.name, "type", to_native(server.server_type.name))
        
        self.inventory.set_variable(server.name, "ipv4", to_native(server.public_net.ipv4.ip))
        self.inventory.set_variable(server.name, "ipv6_network", to_native(server.public_net.ipv6.network))