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##### SUMMARY
The XML got by executing the following playbook was a byte string.

##### playbook

```yaml
---
- name: Get template from zabbix server
  hosts: localhost
  gather_facts: no
  tasks:
    - zabbix_template:
        server_url: "{{ zabbix_server }}"
        login_user: "{{ zabbix_user }}"
        login_password: "{{ zabbix_password }}"
        template_name: Template App Zabbix Proxy
        dump_format: xml
        state: dump
      register: template_xml

    - debug: var=template_xml
```

##### run playbook

```
$ ansible-playbook main.yml
 [WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match 'all'


PLAY [Get template from zabbix server] *****************************************************************************************************************************************

TASK [zabbix_template] *********************************************************************************************************************************************************
ok: [localhost]

TASK [debug] *******************************************************************************************************************************************************************
ok: [localhost] => {
    "template_xml": {
        "changed": false,
        "failed": false,
        "template_xml": "b'<zabbix_export><version>3.0</version><date>....</graphs></zabbix_export>'"
```

In RETURN, the return value is a string.
https://github.com/ansible/ansible/blob/358574d57f2b411e820cbf4d00a8249ac8291cb9/lib/ansible/modules/monitoring/zabbix/zabbix_template.py#L259

So, I think the return value should be a string.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
zabbix_template

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
$ ansible --version
ansible 2.8.5
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/root/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /root/dev/venv/lib64/python3.6/site-packages/ansible
  executable location = /root/dev/venv/bin/ansible
  python version = 3.6.8 (default, Aug  7 2019, 17:28:10) [GCC 4.8.5 20150623 (Red Hat 4.8.5-39)]
```

```
$ pip3 show zabbix-api
Name: zabbix-api
Version: 0.5.4
Summary: Zabbix API
Home-page: https://github.com/gescheit/scripts
Author: Aleksandr Balezin
Author-email: gescheit12@gmail.com
License: GNU LGPL 2.1
Location: /root/dev/venv/lib/python3.6/site-packages
```

```
$ python --version
Python 3.6.8
```

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

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->

```
$ cat /etc/redhat-release
CentOS Linux release 7.6.1810 (Core)
```
template_macros, template_content, template_type):
        """Compares template parameters to already existing values if any are found.
        template_json - JSON structures are compared as deep sorted dictionaries,
        template_xml - XML structures are compared as strings, but filtered and formatted first,
        If none above is used, all the other arguments are compared to their existing counterparts
        retrieved from Zabbix API."""
        changed = False
        
        
        if template_content is not None and template_type == 'xml':
            existing_template = self.dump_template(template_ids, template_type='xml')
            if self.filter_xml_template(template_content) != self.filter_xml_template(existing_template):
                changed = True
            return changed
        existing_template = self.dump_template(template_ids, template_type='json')
        
        if template_content is not None and template_type == 'json':
            parsed_template_json = self.load_json_template(template_content)
            if self.diff_template(parsed_template_json, existing_template):
                changed = True
            return changed
        
        if template_groups is not None:
            existing_groups = [g['name'] for g in existing_template['zabbix_export']['groups']]
            if set(template_groups) != set(existing_groups):
                changed = True