code: def forward(self, x):
      x = self.backbone(x).flatten(start_dim=1)
      x = self.projection_head(x)
      x = nn.functional.normalize(x, dim=1, p=2)
      p = self.prototypes(x)
      return p
  
file_path: lightly/examples/pytorch_lightning/swav.py
imports: import pytorch_lightning
  import torch
  import torchvision
  from torch import nn
  from lightly.loss import SwaVLoss
  from lightly.models.modules import SwaVProjectionHead, SwaVPrototypes
  from lightly.transforms.swav_transform import SwaVTransform
label_desc: Use image node_id 2 for calling the SwaV obj's underlying member method code with example usage: obj.forward(x) and returns: p