Squashed 'pyextra/' changes from 4242801..4348db7

4348db7 add PyJWT we use in backend

git-subtree-dir: pyextra
git-subtree-split: 4348db7e867dafbbcb7ec0302b5528688d1102c6

old-commit-hash: 7ccae06bce

jwt/exceptions.py

@@ -0,0 +1,48 @@
+class InvalidTokenError(Exception):
+    pass
+
+
+class DecodeError(InvalidTokenError):
+    pass
+
+
+class ExpiredSignatureError(InvalidTokenError):
+    pass
+
+
+class InvalidAudienceError(InvalidTokenError):
+    pass
+
+
+class InvalidIssuerError(InvalidTokenError):
+    pass
+
+
+class InvalidIssuedAtError(InvalidTokenError):
+    pass
+
+
+class ImmatureSignatureError(InvalidTokenError):
+    pass
+
+
+class InvalidKeyError(Exception):
+    pass
+
+
+class InvalidAlgorithmError(InvalidTokenError):
+    pass
+
+
+class MissingRequiredClaimError(InvalidTokenError):
+    def __init__(self, claim):
+        self.claim = claim
+
+    def __str__(self):
+        return 'Token is missing the "%s" claim' % self.claim
+
+
+# Compatibility aliases (deprecated)
+ExpiredSignature = ExpiredSignatureError
+InvalidAudience = InvalidAudienceError
+InvalidIssuer = InvalidIssuerError