docs: def add_physical_item(self, instance, item):
          """
          Add a physical item e.g router, cloud etc
  
          :param instance: Hypervisor instance
          :param item: Item to add
          """
          (name, dev_type) = self.device_typename(item)
          self.topology['devices'][name] = {}
          self.topology['devices'][name]['hv_id'] = self.hv_id
          self.topology['devices'][name]['node_id'] = self.nid
          self.topology['devices'][name]['from'] = dev_type['from']
          self.topology['devices'][name]['type'] = dev_type['type']
          self.topology['devices'][name]['desc'] = dev_type['desc']
  
          if 'ext_conf' in dev_type:
              self.topology['devices'][name]['ext_conf'] = dev_type['ext_conf']
  
          for s_item in sorted(self.old_top[instance][item]):
              if self.old_top[instance][item][s_item] is not None:
                  self.topology['devices'][name][s_item] = \
                      self.old_top[instance][item][s_item]
  
          if instance != 'GNS3-DATA' and \
                  self.topology['devices'][name]['type'] == 'Router':
              if 'model' not in self.topology['devices'][name]:
                  self.topology['devices'][name]['model'] = \
                      self.topology['conf'][self.hv_id]['model']
              else:
                  self.topology['devices'][name]['model'] = MODEL_TRANSFORM[
                      self.topology['devices'][name]['model']]
          elif dev_type['type'] == 'VirtualBoxVM':
              self.topology['devices'][name]['vbox_id'] = self.vbox_id
              self.vbox_id += 1
          elif dev_type['type'] == 'QemuVM':
              self.topology['devices'][name]['qemu_id'] = self.qemu_id
              self.qemu_id += 1
  
          if instance != 'GNS3-DATA' \
              and 'hx' not in self.topology['devices'][name] \
                  and 'hy' not in self.topology['devices'][name]:
              self.topology['devices'][name]['hx'] = dev_type['label_x']
              self.topology['devices'][name]['hy'] = -25.0
          self.nid += 1