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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.


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##### 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!!
self.sshpass_pipe = os.pipe()
                        cmd[1] = b'-d' + to_bytes(self.sshpass_pipe[0], nonstring='simplerepr', errors='surrogate_or_strict')
                    display.vvv(u"RETRYING BECAUSE OF CONTROLPERSIST BROKEN PIPE")
                    return_tuple = func(self, *args, **kwargs)
                remaining_retries = remaining_tries - attempt - 1
                _handle_error(remaining_retries, cmd[0], return_tuple, self._play_context.no_log, self.host)
                break
            
            except AnsibleAuthenticationFailure:
                
                raise
            except (AnsibleConnectionFailure, Exception) as e:
                if attempt == remaining_tries - 1:
                    raise
                else:
                    pause = 2 ** attempt - 1
                    if pause > 30:
                        pause = 30
                    if isinstance(e, AnsibleConnectionFailure):
                        msg = u"ssh_retry: attempt: %d, ssh return code is 255. cmd (%s), pausing for %d seconds" % (attempt + 1, cmd_summary, pause)
                    else:
                        msg = (u"ssh_retry: attempt: %d, caught exception(%s) from cmd (%s), "
                               u"pausing for %d seconds" % (attempt + 1, to_text(e), cmd_summary, pause))
                    display.vv(msg, host=self.host)
                    time.sleep(pause)
                    continue
        return return_tuple
    return wrapped
class Connection(ConnectionBase):