@staticmethod
    def add_nodes(xml, nodes):

	network_elems = xml.xpath('//network')
        if 0 > len(network_elems):
            network_elem = network_elems[0]
        elif len(nodes) > 0 and nodes[0].get('component_manager_id'):
            network_urn = nodes[0]['component_manager_id']
            network_elem = xml.add_element('network', name = Xrn(network_urn).get_hrn())
        else:
            network_elem = xml

	
        node_elems = []
        for node in nodes:
            node_fields = ['component_manager_id', 'component_id', 'client_id', 'sliver_id', 'exclusive']
            node_elem = network_elem.add_instance('node', node, node_fields)
            node_elems.append(node_elem)
            # set component name
            if node.get('component_id'):
                component_name = xrn_to_hostname(node['component_id'])
                node_elem.set('component_name', component_name)
	    if node.get('hostname'):
                        simple_elem = node_elem.add_element('hostname')
                        simple_elem.set_text(node['hostname'])
            # set hardware types
	    
            if node.get('hardware_types'):
                for hardware_type in node.get('hardware_types', []):
		    for field in OcfVtServer.fields:	
		        #node_elem.add_instance(field,{field:hardware_type[field]},[])#XXX Ugly notation
			simple_elem = node_elem.add_element(field)
			simple_elem.set_text(hardware_type[field])
            # set location
            if node.get('location'):
                node_elem.add_instance('location', node['location'], Location.fields)       
            # set interfaces
            PGv2Interface.add_interfaces(node_elem, node.get('interfaces'))
            #if node.get('interfaces'):
            #    for interface in  node.get('interfaces', []):
            #        node_elem.add_instance('interface', interface, ['component_id', 'client_id'])
            # set available element
            if node.get('boot_state'):
                if node.get('boot_state').lower() == 'boot':
                    available_elem = node_elem.add_element('available', now='true')
                else:
                    available_elem = node_elem.add_element('available', now='false')
            # add services
	    if node.get('services'):
		for service in node.get('services',[]):
		   fields = service.fields
		   s = node_elem.add_element('service', type=str(service.__class__.__name__))
		   for field in fields:
			if service[field]:
				simple_elem = s.add_element(field)#node_elem.add_element(field)
                        	simple_elem.set_text(service[field])
            #PGv2Services.add_services(node_elem, node.get('services', [])) 
            # add slivers
            slivers = node.get('slivers', [])
            if slivers:
		for sliver in slivers:
			fields = sliver.fields
			s = node_elem.add_element('sliver', type=str(sliver.__class__.__name__))
			for field in fields:
				if sliver[field]:
					simple_elem = s.add_element(field)#node_elem.add_element(field)
                                	simple_elem.set_text(sliver[field])

                # we must still advertise the available sliver types
                #slivers = Sliver({'type': 'plab-vserver'})
                # we must also advertise the available initscripts
                #slivers['tags'] = []
                #if node.get('pl_initscripts'): 
                #    for initscript in node.get('pl_initscripts', []):
                #        slivers['tags'].append({'name': 'initscript', 'value': initscript['name']})
            #PGv2SliverType.add_slivers(node_elem, slivers)
        return node_elems
dataset/ETHPy150Open fp7-ofelia/ocf/ofam/src/src/foam/sfa/rspecs/elements/versions/ocfvtNode.py/OcfVtNode.add_nodes/swapped operands of `>`