**** error of the following after "sudo apt upgrade":
2020-03-13 12:38:43.816936: I tensorflow/stream_executor/platform/default/dso_loader.cc:44] Successfully opened dynamic library libcublas.so.10
2020-03-13 12:38:43.817421: E tensorflow/stream_executor/cuda/cuda_blas.cc:238] failed to create cublas handle: CUBLAS_STATUS_NOT_INITIALIZED
...
2020-03-13 12:38:43.819733: I tensorflow/stream_executor/platform/default/dso_loader.cc:44] Successfully opened dynamic library libcudnn.so.7
2020-03-13 12:38:43.820628: E tensorflow/stream_executor/cuda/cuda_dnn.cc:329] Could not create cudnn handle: CUDNN_STATUS_NOT_INITIALIZED
2020-03-13 12:38:43.820680: E tensorflow/stream_executor/cuda/cuda_dnn.cc:337] Possibly insufficient driver version: 418.87.1

**** try to upgrade nvidia driver since recent driver version is 440 already
$ sudo apt purge nvidia*
$ sudo apt autoremove
$ sudo apt list |grep nvidia
$ sudo apt install nvidia-driver-440