<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
hostname module fails on linux pardus distributions.

##### ISSUE TYPE
- Bug Report

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

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```
3.8.2
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
Pardus Gnu/Linux 19.3


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```
 - name: set hostname
    hostname:
      name: "pardus"
```

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

##### EXPECTED RESULTS
should set hostname on pardus as well


##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```
hostname module cannot be used on platform Linux (pardus)
```

description:
            - Name of the host
        required: true
    use:
        description:
            - Which strategy to use to update the hostname.
            - If not set we try to autodetect, but this can be problematic, particularly with containers as they can present misleading information.
        choices: ['generic', 'debian', 'sles', 'redhat', 'alpine', 'systemd', 'openrc', 'openbsd', 'solaris', 'freebsd']
        version_added: '2.9'
'''
EXAMPLES = '''
- name: Set a hostname
  hostname:
    name: web01
'''
import os
import platform
import socket
import traceback
from ansible.module_utils.basic import (
    AnsibleModule,
    get_distribution,
    get_distribution_version,
)
from ansible.module_utils.common.sys_info import get_platform_subclass
from ansible.module_utils.facts.system.service_mgr import ServiceMgrFactCollector
from ansible.module_utils._text import to_native
STRATS = {'generic': 'Generic', 'debian': 'Debian', 'sles': 'SLES', 'redhat': 'RedHat', 'alpine': 'Alpine',
          'systemd': 'Systemd', 'openrc': 'OpenRC', 'openbsd': 'OpenBSD', 'solaris': 'Solaris', 'freebsd': 'FreeBSD'}
class UnimplementedStrategy(object):