# ansible list in dict (need to understand how it works) **URL:** \ **Category:** Ansible Project\ **Created:** [March 8, 2022, 7:22pm UTC](https://forum.ansible.com/t/ansible-list-in-dict-need-to-understand-how-it-works/36412 "2022-03-08T19:22:04Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![hieronymus](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/hieronymus/32/1624_2.png) [@hieronymus](https://forum.ansible.com/u/hieronymus)\ **Post date:** [March 8, 2022, 7:22pm UTC](https://forum.ansible.com/t/ansible-list-in-dict-need-to-understand-how-it-works/36412/1 "2022-03-08T19:22:04Z")
Hi everyone, I try to understand ansible dictionaries and for my need I use lists in a dictionary which makes the code not simple and I am struggling to understand that: Below there’re part of my playbook and result: user\_list: - name: “name1” city: “New York” phone: “03-45-67” - name: “name2” city: “London” phone: “04-45-67” - name: “name3” city: “Berlin” phone: “05-45-67” I need to retrieve information like each phone number for each name and I found this solution: - name: debugging dict debug: msg: - “type of user\_list: {{ user\_list | type\_debug }}” - " this {{ item[‘name’] }} is relation to this phone : {{ item[‘phone’] }}" loop: “{{ user\_list }}” and here’s the result: TASK [ansible\_dict\_test : debugging dict] \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ok: [localhost] =\> (item={‘name’: ‘name1’, ‘city’: ‘New York’, ‘phone’: ‘03-45-67’}) =\> { “msg”: [ “type of user\_list: list”, " this name1 is relation to this phone : 03-45-67" ] } ok: [localhost] =\> (item={‘name’: ‘name2’, ‘city’: ‘London’, ‘phone’: ‘04-45-67’}) =\> { “msg”: [ “type of user\_list: list”, " this name2 is relation to this phone : 04-45-67" ] } ok: [localhost] =\> (item={‘name’: ‘name3’, ‘city’: ‘Berlin’, ‘phone’: ‘05-45-67’}) =\> { “msg”: [ “type of user\_list: list”, " this name3 is relation to this phone : 05-45-67" ] } I’ve some question about that: 1. type\_debug read from user\_list and it is a dict then why it give a list as result? 2. I has understood, user\_list ist the key of dict and the rest is the value. In that case why item[‘name’] is like a key? 3. Is my playbook good or is a better solution? Thank you in advance for your help because I am really trying to understand in detail how dictionaries work and I need your advice. Best regards, H ---
**Author:** ![vbotka](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/vbotka/32/359_2.png) [@vbotka](https://forum.ansible.com/u/vbotka)\ **Post date:** [March 8, 2022, 11:27pm UTC](https://forum.ansible.com/t/ansible-list-in-dict-need-to-understand-how-it-works/36412/2 "2022-03-08T23:27:32Z")
> 1) type\_debug read from user\_list and it is a dict then why it give a list > as result? The value of the variable \*user\_list\* is a list (you wouldn't be able to iterate it if otherwise)   user\_list:   - city: New York     name: name1     phone: 03-45-67   - city: London     name: name2     phone: 04-45-67   - city: Berlin     name: name3     phone: 05-45-67 > 2) I has understood, user\_list ist the key of dict and the rest is the > value. In that case why item['name'] is like a key? Yes. \*user\_list\* is dictionary (aka hash, or mapping) with one key \*user\_list\*. The value of this key is the list. Each item of this list is a dictionary therefore, in iteration, you can use \*name\* as a key in the dictionary \*item\*. > 3) Is my playbook good or is a better solution? The dictionaries can be searched faster compared to the lists     - set\_fact:         user\_dict: "{{ dict(\_keys|zip(user\_list)) }}"       vars:         \_keys: "{{ user\_list|map(attribute='name')|list }}" transforms the list to a dictionary   phone\_book:     name1:       city: New York       name: name1       phone: 03-45-67     name2:       city: London       name: name2       phone: 04-45-67     name3:       city: Berlin       name: name3       phone: 05-45-67 Now you can easily search by names. If the names alone are not unique create the keys as a combination of attributes     - set\_fact:         phone\_book: "{{ dict(\_keys|zip(\_vals)) }}"       vars:         \_names: "{{ user\_list|map(attribute='name')|list }}"         \_addrs: "{{ user\_list|map(attribute='city')|list }}"         \_keys: "{{ \_names|zip(\_addrs)|map('join', ',')|list }}"         \_vals: "{{ user\_list|map(attribute='phone')|list }}" create keys by joining the name and the city, and values by selecting the phone only   phone\_book:     name1,New York: 03-45-67     name2,London: 04-45-67     name3,Berlin: 05-45-67 You need the bracket notation to reference such keys     phone\_book['name2,London']: 04-45-67 You'll have to stick with the lists if you are not able to create unique keys. ---
**Author:** ![hieronymus](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/hieronymus/32/1624_2.png) [@hieronymus](https://forum.ansible.com/u/hieronymus)\ **Post date:** [March 9, 2022, 3:16pm UTC](https://forum.ansible.com/t/ansible-list-in-dict-need-to-understand-how-it-works/36412/3 "2022-03-09T15:16:55Z")
Thanks a lot for your detailed instructions. I understand dictionnaires much better now but I still have to practice. I know we learn by doing but how do we know what tips or functions we need for a specific case. It is not easy to use something that we don’t know about, by example I didn’t know about zip. So I need to learn the other functions and how to involve them together. Best regards, H