code: def forward(self, x):
      y = self.backbone(x).flatten(start_dim=1)
      z = self.projection_head(y)
      return z
  
file_path: lightly/examples/pytorch_lightning/tico.py
imports: import copy
  import pytorch_lightning
  import torch
  import torchvision
  from torch import nn
  from lightly.loss.tico_loss import TiCoLoss
  from lightly.models.modules.heads import TiCoProjectionHead
  from lightly.models.utils import deactivate_requires_grad, update_momentum
  from lightly.transforms.byol_transform import BYOLTransform, BYOLView1Transform, BYOLView2Transform
  from lightly.utils.scheduler import cosine_schedule
label_desc: Use image node_id 2 for calling the TiCo obj's underlying member method code with example usage: obj.forward(x) and returns: z