code: def get_epoch_lr(cur_epoch):
      """Retrieves the lr for the given epoch according to the policy."""
      # Get lr and scale by by BASE_LR
      lr = get_lr_fun()(cur_epoch) * cfg.OPTIM.BASE_LR
      # Linear warmup
      if cur_epoch < cfg.OPTIM.WARMUP_EPOCHS:
          alpha = cur_epoch / cfg.OPTIM.WARMUP_EPOCHS
          warmup_factor = (
              cfg.OPTIM.WARMUP_FACTOR * (1.0 - alpha) + alpha
          )
          lr *= warmup_factor
      return lr
  
file_path: pycls/pycls/core/optimizer.py
imports: import matplotlib.pyplot
  import numpy
  import torch
  from pycls.core.config import cfg
label_desc: Use image node_id 7 for calling a global function with example usage: get_epoch_lr(cur_epoch) and returns: lr