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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!!
""" converts a Windows path to one that's supported by SFTP and SCP """
        
        prefix = ""
        if re.match(r'^\w{1}:', path):
            prefix = "/"
        
        return "%s%s" % (prefix, path.replace("\\", "/"))
    #
    
    #
    def exec_command(self, cmd, in_data=None, sudoable=True):
        ''' run a command on the remote host '''
        super(Connection, self).exec_command(cmd, in_data=in_data, sudoable=sudoable)
        display.vvv(u"ESTABLISH SSH CONNECTION FOR USER: {0}".format(self._play_context.remote_user), host=self._play_context.remote_addr)
        if getattr(self._shell, "_IS_WINDOWS", False):
            
            
            
            sudoable = False
            
            
            cmd_parts = ["chcp.com", "65001", self._shell._SHELL_REDIRECT_ALLNULL, self._shell._SHELL_AND]
            cmd_parts.extend(self._shell._encode_script(cmd, as_list=True, strict_mode=False, preserve_rc=False))
            cmd = ' '.join(cmd_parts)
        
        
        
        
        ssh_executable = self._play_context.ssh_executable