Match exact string against an array / list - Ansible

The service_name variable prints the following.

"msg": [
    "BLAH PEX",
    "BLAH AEX non prod",
    "BLAH BIND",
    "BLAH DBFactory"
]

I want to match the variable BSA which contains the string BLAH BIND. I tried something like this:

- debug:
    msg: "Match found"
  when: "BSA in service_name"

It works! But the problem is, it also matches if the BSA contains the string BLAH. I want it to only match if there is a exact match. Right now its matching word by word I guess.

Expected Output: It should skip the debug task because when BSA contains the string BLAH, it should not match any strings in the service_name list.

Any help how to achieve to match the entire exact string in the array.

I am using ansible 2.7

Q: "Expected Output: It should skip the debug task because when BSA contains the string BLAH, it should not match any strings in the service_name list."

A: It's working as expected. String "BLAH" doesn't match and the debug task is skipped.

- hosts: localhost
  vars:
    service_name: [ "BLAH PEX", "BLAH AEX non prod", "BLAH BIND", "BLAH DBFactory" ]
    BSA: "BLAH"

  tasks:
    - debug:
        var: service_name
    - debug:
        var: BSA
    - debug:
        msg: "Match found"
      when: "BSA in service_name"
    - debug:
        msg: "Continue"

gives

shell> ansible-playbook playbook.yml

PLAY [localhost] ***

TASK [debug] ***
ok: [localhost] => {
    "service_name": [
        "BLAH PEX", 
        "BLAH AEX non prod", 
        "BLAH BIND", 
        "BLAH DBFactory"
    ]
}

TASK [debug] ***
ok: [localhost] => {
    "BSA": "BLAH"
}

TASK [debug] ***
skipping: [localhost]

TASK [debug] ***
ok: [localhost] => {
    "msg": "Continue"
}

PLAY RECAP ***
localhost: ok=3  changed=0  unreachable=0  failed=0  skipped=1  rescued=0  ignored=0

Update

No quotation is needed in the equivalent below play

shell> cat pb.yml
- hosts: localhost

  vars:

    service_name: [BLAH PEX, BLAH AEX non prod, BLAH BIND, BLAH DBFactory]
    BSA: BLAH

  tasks:

    - debug:
        var: service_name
    
    - debug:
        var: BSA
        
    - debug:
        msg: Match found
      when: BSA in service_name
      
    - debug:
        msg: Continue

and the callback community.general.yaml also needs no quotes to display YAML

shell> ANSIBLE_STDOUT_CALLBACK=yaml ansible-playbook pb.yml

PLAY [localhost] ****************************************************************************************************

TASK [debug] ********************************************************************************************************
ok: [localhost] => 
  service_name:
  - BLAH PEX
  - BLAH AEX non prod
  - BLAH BIND
  - BLAH DBFactory

TASK [debug] ********************************************************************************************************
ok: [localhost] => 
  BSA: BLAH

TASK [debug] ********************************************************************************************************
skipping: [localhost]

TASK [debug] ********************************************************************************************************
ok: [localhost] => 
  msg: Continue

Hint: You can use ansible-lint to remove redundant quotations from the code. For example,

shell> ansible-lint playbook.yml --fix