in logger.py [0:0]
def log(self, key, value, step):
assert key.startswith('train') or key.startswith('eval')
if type(value) == torch.Tensor:
value = value.item()
self._try_sw_log(key, value, step)
mg = self._train_mg if key.startswith('train') else self._eval_mg
mg.log(key, value)