diff --git a/lang/python/src/core.py b/lang/python/src/core.py
index 7003b253..ff68bade 100644
--- a/lang/python/src/core.py
+++ b/lang/python/src/core.py
@@ -762,6 +762,41 @@ class Context(GpgmeWrapper):
         GPGMEError   -- as signaled by the underlying library
 
         """
+        if sign is True:
+            _sign = constants.create.SIGN
+        else:
+            _sign = 0
+
+        if encrypt is True:
+            _encrypt = constants.create.ENCR
+        else:
+            _encrypt = 0
+
+        if certify is True:
+            _certify = constants.create.CERT
+        else:
+            _certify = 0
+
+        if authenticate is True:
+            _authenticate = constants.create.AUTH
+        else:
+            _authenticate = 0
+
+        if passphrase is None:
+            _nopasswd = constants.create.NOPASSWD
+        else:
+            _nopasswd = 0
+
+        if expires is True:
+            _expires = 0
+        else:
+            _expires = constants.create.NOEXPIRE
+
+        if force is True:
+            _force = constants.create.FORCE
+        else:
+            _force = 0
+
         if util.is_a_string(passphrase):
             old_pinentry_mode = self.pinentry_mode
             old_passphrase_cb = getattr(self, '_passphrase_cb', None)
@@ -772,17 +807,10 @@ class Context(GpgmeWrapper):
             self.set_passphrase_cb(passphrase_cb)
 
         try:
-            self.op_createkey(userid, algorithm,
-                              0,  # reserved
-                              expires_in,
-                              None,  # extrakey
-                              ((constants.create.SIGN if sign else 0)
-                               | (constants.create.ENCR if encrypt else 0)
-                               | (constants.create.CERT if certify else 0)
-                               | (constants.create.AUTH if authenticate else 0)
-                               | (constants.create.NOPASSWD if passphrase is None else 0)
-                               | (0 if expires else constants.create.NOEXPIRE)
-                               | (constants.create.FORCE if force else 0)))
+            self.op_createkey(userid, algorithm, 0,  # reserved
+                              expires_in, None,  # extrakey
+                              _sign, _encrypt, _certify, _authenticate,
+                              _nopasswd, _expires, _force)
         finally:
             if util.is_a_string(passphrase):
                 self.pinentry_mode = old_pinentry_mode
@@ -839,6 +867,36 @@ class Context(GpgmeWrapper):
         GPGMEError   -- as signaled by the underlying library
 
         """
+        if sign is True:
+            _sign = constants.create.SIGN
+        else:
+            _sign = 0
+
+        if encrypt is True:
+            _encrypt = constants.create.ENCR
+        else:
+            _encrypt = 0
+
+        if authenticate is True:
+            _authenticate = constants.create.AUTH
+        else:
+            _authenticate = 0
+
+        if passphrase is None:
+            _nopasswd = constants.create.NOPASSWD
+        else:
+            _nopasswd = 0
+
+        if expires is True:
+            _expires = 0
+        else:
+            _expires = constants.create.NOEXPIRE
+
+        if force is True:
+            _force = constants.create.FORCE
+        else:
+            _force = 0
+
         if util.is_a_string(passphrase):
             old_pinentry_mode = self.pinentry_mode
             old_passphrase_cb = getattr(self, '_passphrase_cb', None)
@@ -849,15 +907,9 @@ class Context(GpgmeWrapper):
             self.set_passphrase_cb(passphrase_cb)
 
         try:
-            self.op_createsubkey(key, algorithm,
-                                 0,  # reserved
-                                 expires_in,
-                                 ((constants.create.SIGN if sign else 0)
-                                  | (constants.create.ENCR if encrypt else 0)
-                                  | (constants.create.AUTH if authenticate else 0)
-                                  | (constants.create.NOPASSWD
-                                     if passphrase is None else 0)
-                                  | (0 if expires else constants.create.NOEXPIRE)))
+            self.op_createsubkey(key, algorithm, 0,  # reserved
+                                 expires_in, _sign, _encrypt, _authenticate,
+                                 _nopasswd, _expires, _force)
         finally:
             if util.is_a_string(passphrase):
                 self.pinentry_mode = old_pinentry_mode
@@ -1079,13 +1131,13 @@ class Context(GpgmeWrapper):
         # $ grep '^gpgme_error_t ' obj/lang/python/python3.5-gpg/gpgme.h \
         # | grep -v _op_ | awk "/\(gpgme_ctx/ { printf (\"'%s',\\n\", \$2) } "
         return ((name.startswith('gpgme_op_') and not
-            name.endswith('_result')) or name in {'gpgme_new',
-            'gpgme_set_ctx_flag', 'gpgme_set_protocol',
-            'gpgme_set_sub_protocol', 'gpgme_set_keylist_mode',
-            'gpgme_set_pinentry_mode', 'gpgme_set_locale',
-            'gpgme_ctx_set_engine_info', 'gpgme_signers_add',
-            'gpgme_sig_notation_add', 'gpgme_set_sender', 'gpgme_cancel',
-            'gpgme_cancel_async', 'gpgme_get_key'})
+                 name.endswith('_result')) or name in
+                {'gpgme_new', 'gpgme_set_ctx_flag', 'gpgme_set_protocol',
+                    'gpgme_set_sub_protocol', 'gpgme_set_keylist_mode',
+                    'gpgme_set_pinentry_mode', 'gpgme_set_locale',
+                    'gpgme_ctx_set_engine_info', 'gpgme_signers_add',
+                    'gpgme_sig_notation_add', 'gpgme_set_sender',
+                    'gpgme_cancel', 'gpgme_cancel_async', 'gpgme_get_key'})
 
     _boolean_properties = {'armor', 'textmode', 'offline'}