# Constructing tuple list string with templated variables gets converted to a list of lists

**URL:** <https://forum.ansible.com/t/constructing-tuple-list-string-with-templated-variables-gets-converted-to-a-list-of-lists/45035>\
**Category:** Get Help\
**Tags:** ubuntu, linux\
**Created:** [December 29, 2025, 1:39pm UTC](https://forum.ansible.com/t/constructing-tuple-list-string-with-templated-variables-gets-converted-to-a-list-of-lists/45035 "2025-12-29T13:39:18Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![usaghir](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/usaghir/32/10049_2.png) [@usaghir](https://forum.ansible.com/u/usaghir)\
**Post date:** [December 29, 2025, 1:39pm UTC](https://forum.ansible.com/t/constructing-tuple-list-string-with-templated-variables-gets-converted-to-a-list-of-lists/45035/1 "2025-12-29T13:39:18Z")

</div>

**Constructing tuple list string with templated variables gets converted to a list of lists**

Versions:

```auto
ansible-playbook [core 2.17.6]
python version = 3.13.11
jinja version = 3.1.4

```

I’m trying to automate the configuration of language input sources on a Linux desktop running GNOME. This property is set through `gsettings`/`dconf` and the value looks like the following when English and Japanese are configured:

```auto
$ gsettings get org.gnome.desktop.input-sources sources
[('xkb', 'gb+mac'), ('ibus', 'mozc-jp')]

```

I have tried to construct this list of tuples by looping over a dictionary resembling:

```auto
languages:
  english:
    packages: []
    dconf_source: "('xkb', 'gb+mac')"
  japanese:
    packages: ["ibus-mozc", "mozc-utils-gui"]
    dconf_source: "('ibus', 'mozc-jp')" 

```

and task:

```auto
#### DIDNT WORK
- name: Construct GNOME input sources string
  ansible.builtin.set_fact:
    gnome_input_sources: >-
      [{% for lang in languages.keys() -%}
      {{ languages[lang].dconf_source }}{{ '' if loop.last else ', ' }}
      {%- endfor %}]

- name: Configure GNOME keyboard input sources
  community.general.dconf:
    key: "/org/gnome/desktop/input-sources/sources"
    value: "{{ gnome_input_sources | string }}"
    state: present

```

When this list gets passed over via the dconf module the following is shown when checking dconf and how gsettings interprets the value

```auto
$ dconf read /org/gnome/desktop/input-sources/sources
[['xkb', 'gb+mac'], ['ibus', 'mozc-jp']]
$ gsettings get org.gnome.desktop.input-sources sources
@a(ss) []

```

I am able to use the dconf module when hardcoding the string such as:

```auto
- name: Configure keyboard input source
  community.general.dconf:
    key: "/org/gnome/desktop/input-sources/sources"
    value: "[('xkb', 'gb+mac'), ('ibus', 'mozc-jp')]"
    state: present

```

But I want to be able to have this configurable so that I can add additional input sources in the future.

Any ideas on how to ensure a Ansible doesn’t convert the list of tuples into a list of lists?

---

<div class="post-metadata">

**Author:** ![felixfontein](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/felixfontein/32/7530_2.png) [@felixfontein](https://forum.ansible.com/u/felixfontein)\
**Post date:** [December 29, 2025, 1:45pm UTC](https://forum.ansible.com/t/constructing-tuple-list-string-with-templated-variables-gets-converted-to-a-list-of-lists/45035/2 "2025-12-29T13:45:08Z")

</div>

ansible-core \< 2.19 is notoriously bad at keeping types, it often tries to parse things that look like Python data structures when evaluating templates. If you try this with ansible-core 2.19+, you should get what you expect.

I managed to get this working with 2.17 by adding a dash (or something else that makes it an invalid Python data structure) at the end of `gnome_input_sources`, and removing it when passing it on, like this:

```yaml
    - name: Construct GNOME input sources string
      ansible.builtin.set_fact:
        gnome_input_sources: >-
          [{% for lang in languages.keys() -%}
          {{ languages[lang].dconf_source | string }}{{ '' if loop.last else ', ' }}
          {%- endfor %}]-

    - debug:
        msg: "{{ gnome_input_sources[:-1] | string }}"

```

---

<div class="post-metadata">

**Author:** ![usaghir](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/usaghir/32/10049_2.png) [@usaghir](https://forum.ansible.com/u/usaghir)\
**Post date:** [December 30, 2025, 2:14pm UTC](https://forum.ansible.com/t/constructing-tuple-list-string-with-templated-variables-gets-converted-to-a-list-of-lists/45035/3 "2025-12-30T14:14:13Z")

</div>

Ah perfect, upgrading to ansible-core 2.20 got it working as you mentioned! Also good to know of the workaround for older versions. Thanks for the help 🙂

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/ansible/original/1X/1882d9a01da5d8996a862359b0913cc568a39b84.svg) [@system](https://forum.ansible.com/u/system)\
**Post date:** [January 29, 2026, 2:14pm UTC](https://forum.ansible.com/t/constructing-tuple-list-string-with-templated-variables-gets-converted-to-a-list-of-lists/45035/4 "2026-01-29T14:14:32Z")

</div>

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