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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!!
elif method == 'piped':
                if sftp_action == 'get':
                    
                    
                    (returncode, stdout, stderr) = self.exec_command('dd if=%s bs=%s' % (in_path, BUFSIZE), sudoable=False)
                    with open(to_bytes(out_path, errors='surrogate_or_strict'), 'wb+') as out_file:
                        out_file.write(stdout)
                else:
                    with open(to_bytes(in_path, errors='surrogate_or_strict'), 'rb') as f:
                        in_data = to_bytes(f.read(), nonstring='passthru')
                    if not in_data:
                        count = ' count=0'
                    else:
                        count = ''
                    (returncode, stdout, stderr) = self.exec_command('dd of=%s bs=%s%s' % (out_path, BUFSIZE, count), in_data=in_data, sudoable=False)
            
            if returncode == 0:
                return (returncode, stdout, stderr)
            else:
                
                if len(methods) > 1:
                    display.warning(u'%s transfer mechanism failed on %s. Use ANSIBLE_DEBUG=1 to see detailed information' % (method, host))
                    display.debug(u'%s' % to_text(stdout))
                    display.debug(u'%s' % to_text(stderr))
        if returncode == 255:
            raise AnsibleConnectionFailure("Failed to connect to the host via %s: %s" % (method, to_native(stderr)))
        else:
            raise AnsibleError("failed to transfer file to %s %s:\n%s\n%s" %
                               (to_native(in_path), to_native(out_path), to_native(stdout), to_native(stderr)))
    def _escape_win_path(self, path):