Convert various string literals to bytes.
diff --git a/Lib/binhex.py b/Lib/binhex.py
index 4c53315..e4d551f 100644
--- a/Lib/binhex.py
+++ b/Lib/binhex.py
@@ -38,7 +38,7 @@
 # Various constants
 REASONABLY_LARGE = 32768  # Minimal amount we pass the rle-coder
 LINELEN = 64
-RUNCHAR = chr(0x90)   # run-length introducer
+RUNCHAR = b"\x90"
 
 #
 # This code is no longer byte-order dependent
@@ -351,11 +351,11 @@
         # otherwise: keep 1 byte.
         #
         mark = len(self.pre_buffer)
-        if self.pre_buffer[-3:] == RUNCHAR + '\0' + RUNCHAR:
+        if self.pre_buffer[-3:] == RUNCHAR + b'\0' + RUNCHAR:
             mark = mark - 3
         elif self.pre_buffer[-1] == RUNCHAR:
             mark = mark - 2
-        elif self.pre_buffer[-2:] == RUNCHAR + '\0':
+        elif self.pre_buffer[-2:] == RUNCHAR + b'\0':
             mark = mark - 2
         elif self.pre_buffer[-2] == RUNCHAR:
             pass # Decode all
diff --git a/Lib/test/test_httplib.py b/Lib/test/test_httplib.py
index d9b3b82..bbcdd8b 100644
--- a/Lib/test/test_httplib.py
+++ b/Lib/test/test_httplib.py
@@ -31,13 +31,13 @@
     """
     def read(self, n=-1):
         data = io.BytesIO.read(self, n)
-        if data == '':
+        if data == b'':
             raise AssertionError('caller tried to read past EOF')
         return data
 
     def readline(self, length=None):
         data = io.BytesIO.readline(self, length)
-        if data == '':
+        if data == b'':
             raise AssertionError('caller tried to read past EOF')
         return data
 
diff --git a/Lib/wave.py b/Lib/wave.py
index 6627bcf..42bf8bf 100644
--- a/Lib/wave.py
+++ b/Lib/wave.py
@@ -84,7 +84,7 @@
 
 # Determine endian-ness
 import struct
-if struct.pack("h", 1) == "\000\001":
+if struct.pack("h", 1) == b"\000\001":
     big_endian = 1
 else:
     big_endian = 0