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##### SUMMARY
We seem to be having an issue with eos testing and AttributeError: 'NoneType' object has no attribute 'endswith'.

https://object-storage-ca-ymq-1.vexxhost.net/v1/a0b4156a37f9453eb4ec7db5422272df/ansible_79/61779/2a3bc59e39230ad945d42da08a8aad3f91dee027/third-party-check/ansible-test-network-integration-eos-python37/52a7e42/controller/ansible-debug.html#l48225

It looks like self._get_prompt() is None.

##### ISSUE TYPE
- Bug Report

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

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

```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
zuul.ansible.com
```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->


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

<!--- Paste verbatim command output between quotes -->
```paste below
2019-09-04 20:16:25,014 p=zuul u=31800 | Traceback (most recent call last):
  File "/home/zuul/src/github.com/ansible/ansible/lib/ansible/utils/jsonrpc.py", line 45, in handle_request
    result = rpc_method(*args, **kwargs)
  File "/home/zuul/src/github.com/ansible/ansible/lib/ansible/plugins/connection/network_cli.py", line 389, in update_play_context
    self._terminal.on_become(passwd=auth_pass)
  File "/home/zuul/src/github.com/ansible/ansible/lib/ansible/plugins/terminal/eos.py", line 62, in on_become
    if self._get_prompt().endswith(b'#'):
AttributeError: 'NoneType' object has no attribute 'endswith'
```

super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs)
        self._ssh_shell = None
        self._matched_prompt = None
        self._matched_cmd_prompt = None
        self._matched_pattern = None
        self._last_response = None
        self._history = list()
        self._command_response = None
        self._terminal = None
        self.cliconf = None
        self.paramiko_conn = None
        if self._play_context.verbosity > 3:
            logging.getLogger('paramiko').setLevel(logging.DEBUG)
        if self._network_os:
            self._terminal = terminal_loader.get(self._network_os, self)
            if not self._terminal:
                raise AnsibleConnectionFailure('network os %s is not supported' % self._network_os)
            self.cliconf = cliconf_loader.get(self._network_os, self)
            if self.cliconf:
                self.queue_message('vvvv', 'loaded cliconf plugin for network_os %s' % self._network_os)
                self._sub_plugin = {'type': 'cliconf', 'name': self._network_os, 'obj': self.cliconf}
            else:
                self.queue_message('vvvv', 'unable to load cliconf for network_os %s' % self._network_os)
        else:
            raise AnsibleConnectionFailure(
                'Unable to automatically determine host network os. Please '
                'manually configure ansible_network_os value for this host'
            )
        self.queue_message('log', 'network_os is set to %s' % self._network_os)
    def _get_log_channel(self):