diff --git a/tests/serialize/test_huffman.py b/tests/serialize/test_huffman.py
index 071b3c325..677c6dced 100644
--- a/tests/serialize/test_huffman.py
+++ b/tests/serialize/test_huffman.py
@@ -45,7 +45,7 @@ def test1():
     codec = HuffmanCodec(list(enumerate(probs)))
     
     py_codes = py_encode(dict(enumerate(probs)))
-    py_codes = py_codes.items()
+    py_codes = list(py_codes.items())
     py_codes.sort()
     assert codec.strings == [c for i, c in py_codes]
     
@@ -60,7 +60,7 @@ def test_round_trip():
     strings = list(codec.strings)
     codes = {codec.leaves[i]: strings[i] for i in range(len(codec.leaves))}
     bits = codec.encode(message)
-    string = b''.join(b'{0:b}'.format(ord(c)).rjust(8, b'0')[::-1] for c in bits.as_bytes())
+    string = ''.join('{0:b}'.format(c).rjust(8, '0')[::-1] for c in bits.as_bytes())
     for word in message:
         code = codes[word]
         assert string[:len(code)] == code
@@ -76,7 +76,7 @@ def test_rosetta():
     symb2freq = defaultdict(int)
     for ch in txt:
         symb2freq[ch] += 1
-    by_freq = symb2freq.items()
+    by_freq = list(symb2freq.items())
     by_freq.sort(reverse=True, key=lambda item: item[1])
     symbols = [sym for sym, prob in by_freq]
 
diff --git a/tests/serialize/test_packer.py b/tests/serialize/test_packer.py
index 75394a204..b62b061ba 100644
--- a/tests/serialize/test_packer.py
+++ b/tests/serialize/test_packer.py
@@ -61,7 +61,7 @@ def test_char_packer(vocab):
     bits.seek(0)
     result = [b''] * len(byte_str)
     packer.char_codec.decode(bits, result)
-    assert b''.join(result) == byte_str
+    assert bytearray(result) == byte_str
 
 
 def test_packer_unannotated(tokenizer):
diff --git a/tests/vocab/test_intern.py b/tests/vocab/test_intern.py
index 21296dd2c..6e007c645 100644
--- a/tests/vocab/test_intern.py
+++ b/tests/vocab/test_intern.py
@@ -39,7 +39,7 @@ def test_retrieve_id(sstore):
 
 def test_med_string(sstore):
     nine_char_string = sstore[b'0123456789']
-    assert sstore[nine_char_string] == b'0123456789'
+    assert sstore[nine_char_string] == u'0123456789'
     dummy = sstore[b'A']
     assert sstore[b'0123456789'] == nine_char_string