1 files changed, 2 insertions, 4 deletions
diff --git a/src/test/ed25519_exts_ref.py b/src/test/ed25519_exts_ref.py
index ae537ff15b..dcc0a7c25a 100644
--- a/src/test/ed25519_exts_ref.py
+++ b/src/test/ed25519_exts_ref.py
@@ -53,7 +53,7 @@ def blindPK(pk, param):
 def expandSK(sk):
     h = H(sk)
     a = 2**(b-2) + sum(2**i * bit(h,i) for i in range(3,b-2))
-    k = ''.join([h[i] for i in range(b/8,b/4)])
+    k = bytes(h[i] for i in range(b//8,b//4))
     assert len(k) == 32
     return encodeint(a)+k
 
@@ -64,7 +64,7 @@ def publickeyFromESK(h):
 
 def signatureWithESK(m,h,pk):
     a = decodeint(h[:32])
-    r = Hint(''.join([h[i] for i in range(b/8,b/4)]) + m)
+    r = Hint(bytes([h[i] for i in range(b//8,b//4)]) + m)
     R = scalarmult(B,r)
     S = (r + Hint(encodepoint(R) + pk + m) * a) % l
     return encodepoint(R) + encodeint(S)
@@ -263,5 +263,3 @@ if __name__ == '__main__':
         unittest.main()
     else:
         makeTestVectors()
-
-