Plugin configuration YAML file, not YAML inventory

Raise code

            raise AnsibleParserError(e)

        if not data:
            raise AnsibleParserError('Parsed empty YAML file')
        elif not isinstance(data, MutableMapping):
            raise AnsibleParserError('YAML inventory has invalid structure, it should be a dictionary, got: %s' % type(data))
        elif data.get('plugin'):
            raise AnsibleParserError('Plugin configuration YAML file, not YAML inventory')

        # We expect top level keys to correspond to groups, iterate over them
        # to get host, vars and subgroups (which we iterate over recursivelly)
        if isinstance(data, MutableMapping):
            for group_name in data:
                self._parse_group(group_name, data[group_name])
        else: