convert shebang lines: python -> python3
diff --git a/Demo/scripts/beer.py b/Demo/scripts/beer.py
index 8135509..56eec7b 100755
--- a/Demo/scripts/beer.py
+++ b/Demo/scripts/beer.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # By GvR, demystified after a version by Fredrik Lundh.
 
diff --git a/Demo/scripts/eqfix.py b/Demo/scripts/eqfix.py
index 47c00d3..8d0c8df 100755
--- a/Demo/scripts/eqfix.py
+++ b/Demo/scripts/eqfix.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Fix Python source files to use the new equality test operator, i.e.,
 #       if x = y: ...
diff --git a/Demo/scripts/fact.py b/Demo/scripts/fact.py
index 71fcda2..2a3bef2 100755
--- a/Demo/scripts/fact.py
+++ b/Demo/scripts/fact.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Factorize numbers.
 # The algorithm is not efficient, but easy to understand.
diff --git a/Demo/scripts/find-uname.py b/Demo/scripts/find-uname.py
index 1902423..b6ec1b6 100755
--- a/Demo/scripts/find-uname.py
+++ b/Demo/scripts/find-uname.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """
 For each argument on the command line, look for it in the set of all Unicode
diff --git a/Demo/scripts/from.py b/Demo/scripts/from.py
index 323e684..c8a9346 100755
--- a/Demo/scripts/from.py
+++ b/Demo/scripts/from.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Print From and Subject of messages in $MAIL.
 # Extension to multiple mailboxes and other bells & whistles are left
diff --git a/Demo/scripts/lpwatch.py b/Demo/scripts/lpwatch.py
index 90b3ecf..01d9fea 100755
--- a/Demo/scripts/lpwatch.py
+++ b/Demo/scripts/lpwatch.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Watch line printer queue(s).
 # Intended for BSD 4.3 lpq.
diff --git a/Demo/scripts/makedir.py b/Demo/scripts/makedir.py
index 7095868..a14e848 100755
--- a/Demo/scripts/makedir.py
+++ b/Demo/scripts/makedir.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Like mkdir, but also make intermediate directories if necessary.
 # It is not an error if the given directory already exists (as long
diff --git a/Demo/scripts/markov.py b/Demo/scripts/markov.py
index 990c972..7c08bdb 100755
--- a/Demo/scripts/markov.py
+++ b/Demo/scripts/markov.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 class Markov:
     def __init__(self, histsize, choice):
diff --git a/Demo/scripts/mboxconvert.py b/Demo/scripts/mboxconvert.py
index 2e44f06..cb3ed89 100755
--- a/Demo/scripts/mboxconvert.py
+++ b/Demo/scripts/mboxconvert.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Convert  MH directories (1 message per file) or MMDF mailboxes (4x^A
 # delimited) to unix mailbox (From ... delimited) on stdout.
diff --git a/Demo/scripts/morse.py b/Demo/scripts/morse.py
index 5aacaa1..c2f408f 100755
--- a/Demo/scripts/morse.py
+++ b/Demo/scripts/morse.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # DAH should be three DOTs.
 # Space between DOTs and DAHs should be one DOT.
diff --git a/Demo/scripts/newslist.py b/Demo/scripts/newslist.py
index 9cea1b4..b345f2ef 100755
--- a/Demo/scripts/newslist.py
+++ b/Demo/scripts/newslist.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 #######################################################################
 # Newslist  $Revision$
 #
diff --git a/Demo/scripts/pi.py b/Demo/scripts/pi.py
index 0740cd0..248f81f 100755
--- a/Demo/scripts/pi.py
+++ b/Demo/scripts/pi.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Print digits of pi forever.
 #
diff --git a/Demo/scripts/pp.py b/Demo/scripts/pp.py
index 2c948f7..87b9d8f 100755
--- a/Demo/scripts/pp.py
+++ b/Demo/scripts/pp.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Emulate some Perl command line options.
 # Usage: pp [-a] [-c] [-d] [-e scriptline] [-F fieldsep] [-n] [-p] [file] ...
diff --git a/Demo/scripts/primes.py b/Demo/scripts/primes.py
index d296f0e..c994623 100755
--- a/Demo/scripts/primes.py
+++ b/Demo/scripts/primes.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Print prime numbers in a given range
 
diff --git a/Demo/scripts/queens.py b/Demo/scripts/queens.py
index 726433c..ffd4bea 100755
--- a/Demo/scripts/queens.py
+++ b/Demo/scripts/queens.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 """N queens problem.
 
diff --git a/Demo/scripts/script.py b/Demo/scripts/script.py
index b490b17..a815a35 100755
--- a/Demo/scripts/script.py
+++ b/Demo/scripts/script.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # script.py -- Make typescript of terminal session.
 # Usage:
diff --git a/Demo/scripts/unbirthday.py b/Demo/scripts/unbirthday.py
index af58f8f..b3c7d23 100755
--- a/Demo/scripts/unbirthday.py
+++ b/Demo/scripts/unbirthday.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Calculate your unbirthday count (see Alice in Wonderland).
 # This is defined as the number of days from your birth until today
diff --git a/Demo/scripts/update.py b/Demo/scripts/update.py
index d49e4b3..49c09d8 100755
--- a/Demo/scripts/update.py
+++ b/Demo/scripts/update.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Update a bunch of files according to a script.
 # The input file contains lines of the form <filename>:<lineno>:<text>,