fix to_bytes()

common.py

@@ -27,10 +27,10 @@ def to_bits(bytes_list):
             mask = 1 << i
             yield (1 if (val & mask) else 0)
 
-
-def to_bytes(bits):
+bit_weights = [1 << i for i in range(8)]
+def to_byte(bits):
     assert len(bits) == 8
-    byte = sum(b << i for i, b in enumerate(bits))
+    byte = int(np.dot(bits, bit_weights))
     return chr(byte)
 
 def load(fname):