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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 _get_nics(dom):
    '''
    Get domain network interfaces from a libvirt domain object.
    '''
    nics = {}
    doc = ElementTree.fromstring(dom.XMLDesc(0))
    for iface_node in doc.findall('devices/interface'):
        nic = {}
        nic['type'] = iface_node.get('type')
        for v_node in iface_node:
            if v_node.tag == 'mac':
                nic['mac'] = v_node.get('address')
            if v_node.tag == 'model':
                nic['model'] = v_node.get('type')
            if v_node.tag == 'target':
                nic['target'] = v_node.get('dev')
            # driver, source, and match can all have optional attributes
            if re.match('(driver|source|address)', v_node.tag):
                temp = {}
                for key, value in six.iteritems(v_node.attrib):
                    temp[key] = value
                nic[v_node.tag] = temp
            # virtualport needs to be handled separately, to pick up the
            # type attribute of the virtualport itself
            if v_node.tag == 'virtualport':
                temp = {}
                temp['type'] = v_node.get('type')
                for key, value in six.iteritems(v_node.attrib):
                    temp[key] = value
                nic['virtualport'] = temp
        if 'mac' not in nic:
            continue
        nics[nic['mac']] = nic
    return nics