Using become in ansible locally – CentOS

I am trying to understand –become in order to use ansible to do some local task on my centos. I tried several ansible modules (copy, unarchive) with become that each result with diffetent kind of errors.

Platform used: centos 7

Ansible (installed in a python 3 virtual env) version:

(ansible) [maadam@linux update_centos]$ ansible --version
ansible 2.10.16
  config file = None
  configured module search path = ['/home/maadam/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/maadam/Sources/python/venv/ansible/lib64/python3.6/site-packages/ansible
  executable location = /home/maadam/Sources/python/venv/ansible/bin/ansible
  python version = 3.6.8 (default, Nov 16 2020, 16:55:22) [GCC 4.8.5 20150623 (Red Hat 4.8.5-44)]

I tried to reproduice the example provided by @techraf in this issue to test become: Using –become for ansible_connection=local.

I used the same playbook:

---
- hosts: localhost
  gather_facts: no
  connection: local
  tasks:
    - command: whoami
      register: whoami
    - debug:
        var: whoami.stdout

So I hope the same result as this:

(ansible) [maadam@linux update_centos]$ sudo whoami
root

Whithout become:

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

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

TASK [command] *****************************************************************************************
changed: [localhost]

TASK [debug] *******************************************************************************************
ok: [localhost] => {
    "whoami.stdout": "maadam"
}

PLAY RECAP *********************************************************************************************
localhost                  : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   

With become I have this error:

(ansible) [maadam@linux update_centos]$ ansible-playbook playbook.yml --become
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost
does not match 'all'

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

TASK [command] *****************************************************************************************
fatal: [localhost]: FAILED! => {"changed": false, "module_stderr": "/var/tmp/sclPip796: line 8: -H: command not foundn", "module_stdout": "", "msg": "MODULE FAILUREnSee stdout/stderr for the exact error", "rc": 127}

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

So I don’t understand what I am missing with become.

Thanks for your helps