diff -u -r source.orig/src/vizhp2p source/src/vizhp2p
--- source.orig/src/vizhp2p	1970-01-01 01:00:01.000000000 +0100
+++ source/src/vizhp2p	2021-08-24 10:41:42.926881770 +0200
@@ -94,25 +94,25 @@
             with open(hostfile) as fd:
                 for line in fd:
                     if line.startswith(motif_rank):
-                        print line
+                        print(line)
                         c,v = line[len(motif_rank)+1:-1].split(separator)
                         nodes[c] = v
                         
         # display k worst nodes indices
-        print "\nTop %d bad mean:" % k
+        print("\nTop %d bad mean:" % k)
         mean_order = np.argsort(a_mean)
-        print [nodes[str(c)] for c in mean_order[:k]]
+        print([nodes[str(c)] for c in mean_order[:k]])
         mean_st = "Top nodes with bad mean:\n"
         for i in range(0, k, hostname_per_line):
             mean_st += repr([nodes[str(c)] for c 
                              in mean_order[i:i + hostname_per_line]]) + "\n"
 
-        print "Top %d bad std:" % k
-        print [nodes[str(c)] for c in np.argsort(a_std)[-k:][::-1]]
+        print("Top %d bad std:" % k)
+        print([nodes[str(c)] for c in np.argsort(a_std)[-k:][::-1]])
 
-        print "Top %d bad mean/std:" % k
+        print("Top %d bad mean/std:" % k)
         pen_order = np.argsort(a_mean / a_std)
-        print [nodes[str(c)] for c in pen_order[:k]]
+        print([nodes[str(c)] for c in pen_order[:k]])
         pen_st = "Top nodes with bad mean/std:\n"
         for i in range(0, k, hostname_per_line):
             pen_st += repr([nodes[str(c)] for c 
@@ -293,9 +293,9 @@
 # and 'p' (snapshot) 
 def onrefresh(event):
     if event.key == 'r':
-        print "refreshing...",
+        print("refreshing...", end=' ')
         loop()
-        print "ok"
+        print("ok")
     elif event.key == 'q':
         exit()
     elif event.key == 'p':
@@ -303,9 +303,9 @@
         fig1.savefig(snapfile)
         snapfile = outputname + "_snapshot_time.png"
         fig2.savefig(snapfile)
-        print 'snapshot saved (%s)' % snapfile
+        print('snapshot saved (%s)' % snapfile)
     else:
-        print "The answer to %s is 42." % event.key
+        print("The answer to %s is 42." % event.key)
 
 
 if __name__ == "__main__":
@@ -356,11 +356,11 @@
         countfile = outputname + ".count.bin"
 
     print("visu_hp2p configuration:")
-    print("   DATAFILE            : %s"%resfile)
-    print("   BIN_TIMER_FILE      : %s"%resfile_time)
-    print("   HOSTFILE            : %s"%hostfile)
-    print("   Bad nodes to display: %d"%k)
-    print("   GUI resolution      : %s"%resolution)
+    print(("   DATAFILE            : %s"%resfile))
+    print(("   BIN_TIMER_FILE      : %s"%resfile_time))
+    print(("   HOSTFILE            : %s"%hostfile))
+    print(("   Bad nodes to display: %d"%k))
+    print(("   GUI resolution      : %s"%resolution))
 
     hostname_per_line = 4 # for GUI layout
     refresh_in_sec = 60
@@ -377,7 +377,7 @@
     # wait for resfile
     while not os.path.exists(resfile) :
         time.sleep(5)
-        print "Waiting for input files..."
+        print("Waiting for input files...")
 
     # add callback on key press event
     cid1 = fig1.canvas.mpl_connect('key_press_event', onrefresh)
Only in source/src: vizhp2p.bak
diff -u -r source.orig/src/vizhp2p_html source/src/vizhp2p_html
--- source.orig/src/vizhp2p_html	1970-01-01 01:00:01.000000000 +0100
+++ source/src/vizhp2p_html	2021-08-24 10:41:54.799946303 +0200
@@ -118,7 +118,7 @@
     hostfile = args.hostfile
     clustername = args.clustername
     if len(args.OutputName) == 0:
-        print "No DATAFILE given! Please provide Hp2p output files name !"
+        print("No DATAFILE given! Please provide Hp2p output files name !")
         exit(0)
     else:
         outputname = args.OutputName.split('.')[0]
@@ -134,13 +134,13 @@
         else:
             outfile = args.outfile
 
-    print "%s configuration:"%commandname
-    print "   DATAFILE            : %s"%resfile
-    print "   HOSTFILE            : %s"%hostfile
-    print "   CLUSTER             : %s"%clustername
-    print "   OUTPUTFILE          : %s"%outfile
+    print("%s configuration:"%commandname)
+    print("   DATAFILE            : %s"%resfile)
+    print("   HOSTFILE            : %s"%hostfile)
+    print("   CLUSTER             : %s"%clustername)
+    print("   OUTPUTFILE          : %s"%outfile)
     if not os.path.exists(resfile):
-        print "%s doesn't exist...Exiting"%resfile
+        print("%s doesn't exist...Exiting"%resfile)
         exit(0)
 
 # Data management
Only in source/src: vizhp2p_html.bak