diff --git a/examples/python/jobshop_ft06_distance_sat.py b/examples/python/jobshop_ft06_distance_sat.py
index 5fd7a73d74..a0edaa02bd 100755
--- a/examples/python/jobshop_ft06_distance_sat.py
+++ b/examples/python/jobshop_ft06_distance_sat.py
@@ -102,16 +102,16 @@ def jobshop_ft06_distance():
         for j1 in range(len(job_intervals)):
             # Initial arc from the dummy node (0) to a task.
             start_lit = model.NewBoolVar("%i is first job" % j1)
-            arcs.append([0, j1 + 1, start_lit])
+            arcs.append((0, j1 + 1, start_lit))
             # Final arc from an arc to the dummy node.
-            arcs.append([j1 + 1, 0, model.NewBoolVar("%i is last job" % j1)])
+            arcs.append((j1 + 1, 0, model.NewBoolVar("%i is last job" % j1)))
 
             for j2 in range(len(job_intervals)):
                 if j1 == j2:
                     continue
 
                 lit = model.NewBoolVar("%i follows %i" % (j2, j1))
-                arcs.append([j1 + 1, j2 + 1, lit])
+                arcs.append((j1 + 1, j2 + 1, lit))
 
                 # We add the reified precedence to link the literal with the
                 # times of the two tasks.
diff --git a/examples/python/prize_collecting_tsp_sat.py b/examples/python/prize_collecting_tsp_sat.py
index 2ddff9b380..1b5b2841ea 100755
--- a/examples/python/prize_collecting_tsp_sat.py
+++ b/examples/python/prize_collecting_tsp_sat.py
@@ -1762,7 +1762,7 @@ def prize_collecting_tsp():
     arcs = []
     for i in all_nodes:
         is_visited = model.NewBoolVar(f"{i} is visited")
-        arcs.append([i, i, is_visited.Not()])
+        arcs.append((i, i, is_visited.Not()))
 
         obj_vars.append(is_visited)
         obj_coeffs.append(VISIT_VALUES[i])
@@ -1773,7 +1773,7 @@ def prize_collecting_tsp():
                 used_arcs[i, j] = is_visited.Not()
                 continue
             arc_is_used = model.NewBoolVar(f"{j} follows {i}")
-            arcs.append([i, j, arc_is_used])
+            arcs.append((i, j, arc_is_used))
 
             obj_vars.append(arc_is_used)
             obj_coeffs.append(-DISTANCE_MATRIX[i][j])
diff --git a/examples/python/prize_collecting_vrp_sat.py b/examples/python/prize_collecting_vrp_sat.py
index 41d6ea5d7e..69dc2c6752 100755
--- a/examples/python/prize_collecting_vrp_sat.py
+++ b/examples/python/prize_collecting_vrp_sat.py
@@ -1776,7 +1776,7 @@ def prize_collecting_vrp():
         arcs = []
         for i in all_nodes:
             is_visited = model.NewBoolVar(f"{i} is visited")
-            arcs.append([i, i, is_visited.Not()])
+            arcs.append((i, i, is_visited.Not()))
 
             obj_vars.append(is_visited)
             obj_coeffs.append(VISIT_VALUES[i])
@@ -1787,7 +1787,7 @@ def prize_collecting_vrp():
                     used_arcs[v][i, j] = is_visited.Not()
                     continue
                 arc_is_used = model.NewBoolVar(f"{j} follows {i}")
-                arcs.append([i, j, arc_is_used])
+                arcs.append((i, j, arc_is_used))
 
                 obj_vars.append(arc_is_used)
                 obj_coeffs.append(-DISTANCE_MATRIX[i][j])
diff --git a/examples/python/single_machine_scheduling_with_setup_release_due_dates_sat.py b/examples/python/single_machine_scheduling_with_setup_release_due_dates_sat.py
index b82ed3719d..2381de7831 100644
--- a/examples/python/single_machine_scheduling_with_setup_release_due_dates_sat.py
+++ b/examples/python/single_machine_scheduling_with_setup_release_due_dates_sat.py
@@ -449,19 +449,19 @@ def single_machine_scheduling():
     for i in all_jobs:
         # Initial arc from the dummy node (0) to a task.
         start_lit = model.NewBoolVar("")
-        arcs.append([0, i + 1, start_lit])
+        arcs.append((0, i + 1, start_lit))
         # If this task is the first, set to minimum starting time.
         min_start_time = max(release_dates[i], setup_times[0][i])
         model.Add(starts[i] == min_start_time).OnlyEnforceIf(start_lit)
         # Final arc from an arc to the dummy node.
-        arcs.append([i + 1, 0, model.NewBoolVar("")])
+        arcs.append((i + 1, 0, model.NewBoolVar("")))
 
         for j in all_jobs:
             if i == j:
                 continue
 
             lit = model.NewBoolVar("%i follows %i" % (j, i))
-            arcs.append([i + 1, j + 1, lit])
+            arcs.append((i + 1, j + 1, lit))
 
             # We add the reified precedence to link the literal with the times of the
             # two tasks.
diff --git a/examples/python/tsp_sat.py b/examples/python/tsp_sat.py
index ebca05fcc2..b94d348b08 100644
--- a/examples/python/tsp_sat.py
+++ b/examples/python/tsp_sat.py
@@ -1721,7 +1721,7 @@ def main():
                 continue
 
             lit = model.NewBoolVar("%i follows %i" % (j, i))
-            arcs.append([i, j, lit])
+            arcs.append((i, j, lit))
             arc_literals[i, j] = lit
 
             obj_vars.append(lit)