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##### SUMMARY
If you don't have an ssh client installed in container image or on your system, ansible just throws following error -  `The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'` error. 

```
TASK [Gathering Facts] *********************************************************
[WARNING]: Unhandled error in Python interpreter discovery for host <hostname1>: [Errno 2] No such file or directory: b'ssh': b'ssh'

[WARNING]: Unhandled error in Python interpreter discovery for host <hostname2>: [Errno 2] No such file or directory: b'ssh': b'ssh'

An exception occurred during task execution. To see the full traceback, use -vvv. The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'
fatal: [<hostname1>]: FAILED! => {"msg": "Unexpected failure during module execution.", "stdout": ""}

An exception occurred during task execution. To see the full traceback, use -vvv. The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'
fatal: [<hostname2>]: FAILED! => {"msg": "Unexpected failure during module execution.", "stdout": ""}
```

##### ISSUE TYPE
- Bug Report

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

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
2.9.6
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
Run playbook on the system where ssh client is not installed & playbook is expecting to use ssh keys for remote hosts.


<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
If possible adding an error message indicating `ssh client is not installed on the system`

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

<!--- Paste verbatim command output between quotes -->
```paste below
Error message mentioned in the summary 
The error was: FileNotFoundError: [Errno 2] No such file or directory: b'ssh': b'ssh'
```

Thank you!!
- name: ANSIBLE_SSH_CONTROL_PATH
        ini:
          - key: control_path
            section: ssh_connection
        vars:
          - name: ansible_control_path
            version_added: '2.7'
      control_path_dir:
        default: ~/.ansible/cp
        description:
          - This sets the directory to use for ssh control path if the control path setting is null.
          - Also, provides the `%(directory)s` variable for the control path setting.
        env:
          - name: ANSIBLE_SSH_CONTROL_PATH_DIR
        ini:
          - section: ssh_connection
            key: control_path_dir
        vars:
          - name: ansible_control_path_dir
            version_added: '2.7'
      sftp_batch_mode:
        default: 'yes'
        description: 'TODO: write it'
        env: [{name: ANSIBLE_SFTP_BATCH_MODE}]
        ini:
        - {key: sftp_batch_mode, section: ssh_connection}
        type: bool
        vars:
          - name: ansible_sftp_batch_mode
            version_added: '2.7'