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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'
```

escalation on platforms that support it.  Normally this means
        transitioning from user mode to C(enable) mode in the CLI session.
        If become is set to True and the remote device does not support
        privilege escalation or the privilege has already been elevated, then
        this option is silently ignored.
      - Can be configured from the CLI via the C(--become) or C(-b) options.
    default: False
    ini:
      - section: privilege_escalation
        key: become
    env:
      - name: ANSIBLE_BECOME
    vars:
      - name: ansible_become
  become_method:
    description:
      - This option allows the become method to be specified in for handling
        privilege escalation.  Typically the become_method value is set to
        C(enable) but could be defined as other values.
    default: sudo
    ini:
      - section: privilege_escalation
        key: become_method
    env:
      - name: ANSIBLE_BECOME_METHOD
    vars:
      - name: ansible_become_method
  host_key_auto_add:
    type: boolean
    description: