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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def cpu_baseline(full=False, migratable=False, out='libvirt', **kwargs):
    '''
    Return the optimal 'custom' CPU baseline config for VM's on this minion

    .. versionadded:: 2016.3.0

    :param full: Return all CPU features rather than the ones on top of the closest CPU model
    :param migratable: Exclude CPU features that are unmigratable (libvirt 2.13+)
    :param out: 'libvirt' (default) for usable libvirt XML definition, 'salt' for nice dict
    :param connection: libvirt connection URI, overriding defaults

        .. versionadded:: 2019.2.0
    :param username: username to connect with, overriding defaults

        .. versionadded:: 2019.2.0
    :param password: password to connect with, overriding defaults

        .. versionadded:: 2019.2.0

    CLI Example:

    .. code-block:: bash

        salt '*' virt.cpu_baseline

    '''
    conn = __get_conn(**kwargs)
    caps = ElementTree.fromstring(conn.getCapabilities())
    cpu = caps.find('host/cpu')
    log.debug('Host CPU model definition: %s', salt.utils.stringutils.to_str(ElementTree.tostring(cpu)))

    flags = 0
    if migratable:
        # This one is only in 1.2.14+
        if getattr(libvirt, 'VIR_CONNECT_BASELINE_CPU_MIGRATABLE', False):
            flags += libvirt.VIR_CONNECT_BASELINE_CPU_MIGRATABLE
        else:
            conn.close()
            raise ValueError

    if full and getattr(libvirt, 'VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES', False):
        # This one is only in 1.1.3+
        flags += libvirt.VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES

    cpu = ElementTree.fromstring(conn.baselineCPU([salt.utils.stringutils.to_str(ElementTree.tostring(cpu))], flags))
    conn.close()

    if full and not getattr(libvirt, 'VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES', False):
        # Try do it by ourselves
        # Find the models in cpu_map.xml and iterate over them for as long as entries have submodels
        with salt.utils.files.fopen('/usr/share/libvirt/cpu_map.xml', 'r') as cpu_map:
            cpu_map = ElementTree.parse(cpu_map)

        cpu_model = cpu.find('model').text
        while cpu_model:
            cpu_map_models = cpu_map.findall('arch/model')
            cpu_specs = [el for el in cpu_map_models if el.get('name') == cpu_model and bool(len(el))]

            if not cpu_specs:
                raise ValueError('Model {0} not found in CPU map'.format(cpu_model))
            elif len(cpu_specs) > 1:
                raise ValueError('Multiple models {0} found in CPU map'.format(cpu_model))

            cpu_specs = cpu_specs[0]

            # libvirt's cpu map used to nest model elements, to point the parent model.
            # keep this code for compatibility with old libvirt versions
            model_node = cpu_specs.find('model')
            if model_node is None:
                cpu_model = None
            else:
                cpu_model = model_node.get('name')

            cpu.extend([feature for feature in cpu_specs.findall('feature')])

    if out == 'salt':
        return {
            'model': cpu.find('model').text,
            'vendor': cpu.find('vendor').text,
            'features': [feature.get('name') for feature in cpu.findall('feature')]
        }
    return cpu.toxml()