add tf bert files

pytorch_transformers/file_utils.py

@@ -79,6 +79,9 @@ def url_to_filename(url, etag=None):
     Convert `url` into a hashed filename in a repeatable way.
     If `etag` is specified, append its hash to the url's, delimited
     by a period.
+    If the url ends with .h5 (Keras HDF5 weights) ands '.h5' to the name
+    so that TF 2.0 can identify it as a HDF5 file
+    (see https://github.com/tensorflow/tensorflow/blob/00fad90125b18b80fe054de1055770cfb8fe4ba3/tensorflow/python/keras/engine/network.py#L1380)
     """
     url_bytes = url.encode('utf-8')
     url_hash = sha256(url_bytes)
@@ -89,6 +92,9 @@ def url_to_filename(url, etag=None):
         etag_hash = sha256(etag_bytes)
         filename += '.' + etag_hash.hexdigest()
 
+    if url.endswith('.h5'):
+        filename += '.h5'
+
     return filename