torch.Tensor.bfloat16
Tensor.bfloat16(memory_format=torch.preserve_format) -> Tensor
"self.bfloat16()" is equivalent to "self.to(torch.bfloat16)". See
   "to()".
Parameters:
      memory_format ("torch.memory_format", optional) -- the
      desired memory format of returned Tensor. Default:
      "torch.preserve_format".