Fix findnocoding.p and pysource.py scripts

I suppose that these scripts didn't work since Python 3.0.
diff --git a/Tools/scripts/pysource.py b/Tools/scripts/pysource.py
index c7dbe60..7348a68 100755
--- a/Tools/scripts/pysource.py
+++ b/Tools/scripts/pysource.py
@@ -22,7 +22,7 @@
 
 import os, re
 
-binary_re = re.compile('[\x00-\x08\x0E-\x1F\x7F]')
+binary_re = re.compile(br'[\x00-\x08\x0E-\x1F\x7F]')
 
 debug = False
 
@@ -42,7 +42,7 @@
         return None
 
     try:
-        return open(fullpath)
+        return open(fullpath, "rb")
     except IOError as err: # Access denied, or a special file - ignore it
         print_debug("%s: access denied: %s" % (fullpath, err))
         return None
@@ -65,7 +65,7 @@
 
     if fullpath.endswith(".py") or fullpath.endswith(".pyw"):
         return True
-    elif "python" in line:
+    elif b"python" in line:
         # disguised Python script (e.g. CGI)
         return True