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##### SUMMARY
<!--- Explain the problem briefly below -->
Unit tests for ios_interfaces is failing, with import error

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
ios_interfaces
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
devel
```

##### 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. -->
macos

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

<!--- Paste example playbooks or commands between quotes below -->
```yaml

```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
Unit tests for `ios_interfaces` should pass w/o any issue/failure

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
Unit tests are failing with error: `ImportError: cannot import name 'dict_diff' from 'ansible.module_utils.network.ios.utils.utils'`
<!--- Paste verbatim command output between quotes -->
```paste below

```

""" The command generator when state is deleted
        :param want: the objects from which the configuration should be removed
        :param obj_in_have: the current configuration as a dictionary
        :param interface_type: interface type
        :rtype: A list
        :returns: the commands necessary to remove the current configuration
                  of the provided objects
        """
        commands = []
        if want:
            for interface in want:
                for each in have:
                    if each['name'] == interface['name']:
                        break
                else:
                    continue
                interface = dict(name=interface['name'])
                commands.extend(self._clear_config(interface, each))
        else:
            for each in have:
                want = dict()
                commands.extend(self._clear_config(want, each))
        return commands
    def _set_config(self, want, have):