I also ran the following code https://github.com/huggingface/pytorch-pretrained-BERT/blob/master/examples/extract_features.py 151
though it does not seem very straightforward to interpret the output:
$ python extract_features.py --input_file test_bert.txt --output_file out_bert.txt --bert_model bert-base-uncased
$ cat test_bert.txt 
My name is mona jalal and I live in boston