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##### SUMMARY
Ansible in dnf.py uses a private attributes (in this case it is an internal cache for security filters - base._update_security_filters). Using private attributes could result in random fails, because they could be even removed without announcement because it is not API.


        filters = []
        if self.bugfix:
            key = {'advisory_type__eq': 'bugfix'}
            filters.append(base.sack.query().upgrades().filter(**key))
        if self.security:
            key = {'advisory_type__eq': 'security'}
            filters.append(base.sack.query().upgrades().filter(**key))
        if filters:
            base._update_security_filters = filters

Also I an not sure if it works like expected (there is a difference in dnf upgrade, and dnf upgrade-minimal) and I don't know what was expected from ansible.

I also propose a new API in dnf that could resolve the issue (https://github.com/rpm-software-management/dnf/pull/1715). Any comment or suggestion is welcome
 
##### ISSUE TYPE
- Bug Report

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

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

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

```

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


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

<!--- Paste example playbooks or commands between quotes below -->
```yaml

```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->


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

<!--- Paste verbatim command output between quotes -->
```paste below

```

- If C(yes) it allows  erasing  of  installed  packages to resolve dependencies.
    required: false
    type: bool
    default: "no"
    version_added: "2.10"
  nobest:
    description:
      - Set best option to False, so that transactions are not limited to best candidates only.
    required: false
    type: bool
    default: "no"
    version_added: "2.11"
  cacheonly:
    description:
      - Tells dnf to run entirely from system cache; does not download or update metadata.
    type: bool
    default: "no"
    version_added: "2.12"
notes:
  - When used with a `loop:` each package will be processed individually, it is much more efficient to pass the list directly to the `name` option.
  - Group removal doesn't work if the group was installed with Ansible because
    upstream dnf's API doesn't properly mark groups as installed, therefore upon
    removal the module is unable to detect that the group is installed
    (https://bugzilla.redhat.com/show_bug.cgi?id=1620324)
requirements:
  - "python >= 2.6"
  - python-dnf
  - for the autoremove option you need dnf >= 2.0.1"
author:
  - Igor Gnatenko (@ignatenkobrain) <i.gnatenko.brain@gmail.com>