Fix compatibility with cryptography 3.4.x

src/pretix/base/secrets.py

@@ -4,7 +4,7 @@ import struct
 
 from cryptography.hazmat.backends.openssl.backend import Backend
 from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
-from cryptography.hazmat.primitives.serialization.base import (
+from cryptography.hazmat.primitives.serialization import (
     Encoding, NoEncryption, PrivateFormat, PublicFormat, load_pem_private_key,
     load_pem_public_key,
 )

src/requirements/production.txt

@@ -69,5 +69,5 @@ packaging
 tlds>=2020041600
 text-unidecode==1.*
 protobuf==3.13.*
-cryptography
+cryptography>=3.4.2
 sepaxml==2.4.*,>=2.4.1

src/setup.py

@@ -155,7 +155,7 @@ setup(
         'tlds>=2020041600',
         'text-unidecode==1.*',
         'protobuf==3.13.*',
-        'cryptography',
+        'cryptography>=3.4.2',
         'sepaxml==2.4.*,>=2.4.1',
     ],
     extras_require={