Added an is_jwt function.

Author: rohe

src/cryptojwt/utils.py

@@ -1,13 +1,13 @@
 import base64
+from binascii import unhexlify
+from email.message import EmailMessage
 import functools
 import importlib
 import json
 import re
 import struct
-import warnings
-from binascii import unhexlify
-from email.message import EmailMessage
 from typing import List
+import warnings
 
 from cryptojwt.exception import BadSyntax
 
@@ -357,3 +357,11 @@ def is_json_jws(token):
             return False
 
     return True
+
+
+def is_jws(token):
+    if is_json_jws(token):
+        return 'json'
+    elif is_compact_jws(token):
+        return 'compact'
+    return False