Replace backticks with repr() or "%r"

From SF patch #852334.
diff --git a/Demo/scripts/eqfix.py b/Demo/scripts/eqfix.py
index 583d54e..2139d2b 100755
--- a/Demo/scripts/eqfix.py
+++ b/Demo/scripts/eqfix.py
@@ -58,12 +58,12 @@
 	return ispythonprog.match(name) >= 0
 
 def recursedown(dirname):
-	dbg('recursedown(' + `dirname` + ')\n')
+	dbg('recursedown(%r)\n' % (dirname,))
 	bad = 0
 	try:
 		names = os.listdir(dirname)
 	except os.error, msg:
-		err(dirname + ': cannot list directory: ' + `msg` + '\n')
+		err('%s: cannot list directory: %r\n' % (dirname, msg))
 		return 1
 	names.sort()
 	subdirs = []
@@ -80,11 +80,11 @@
 	return bad
 
 def fix(filename):
-##	dbg('fix(' + `filename` + ')\n')
+##	dbg('fix(%r)\n' % (dirname,))
 	try:
 		f = open(filename, 'r')
 	except IOError, msg:
-		err(filename + ': cannot open: ' + `msg` + '\n')
+		err('%s: cannot open: %r\n' % (filename, msg))
 		return 1
 	head, tail = os.path.split(filename)
 	tempname = os.path.join(head, '@' + tail)
@@ -122,14 +122,13 @@
 					g = open(tempname, 'w')
 				except IOError, msg:
 					f.close()
-					err(tempname+': cannot create: '+\
-					    `msg`+'\n')
+					err('%s: cannot create: %r\n' % (tempname, msg))
 					return 1
 				f.seek(0)
 				lineno = 0
 				rep(filename + ':\n')
 				continue # restart from the beginning
-			rep(`lineno` + '\n')
+			rep(repr(lineno) + '\n')
 			rep('< ' + line)
 			rep('> ' + newline)
 		if g is not None:
@@ -146,17 +145,17 @@
 		statbuf = os.stat(filename)
 		os.chmod(tempname, statbuf[ST_MODE] & 07777)
 	except os.error, msg:
-		err(tempname + ': warning: chmod failed (' + `msg` + ')\n')
+		err('%s: warning: chmod failed (%r)\n' % (tempname, msg))
 	# Then make a backup of the original file as filename~
 	try:
 		os.rename(filename, filename + '~')
 	except os.error, msg:
-		err(filename + ': warning: backup failed (' + `msg` + ')\n')
+		err('%s: warning: backup failed (%r)\n' % (filename, msg))
 	# Now move the temp file to the original file
 	try:
 		os.rename(tempname, filename)
 	except os.error, msg:
-		err(filename + ': rename failed (' + `msg` + ')\n')
+		err('%s: rename failed (%r)\n' % (filename, msg))
 		return 1
 	# Return succes
 	return 0