diff --git a/examples/demo.py b/examples/demo.py
index a6b13572fcfb81383dcef4739d9c953657c1ef25..e9f4e294320fbf94e6555a15ae2811b54cdbfc0f 100644
--- a/examples/demo.py
+++ b/examples/demo.py
@@ -5,7 +5,6 @@ import time
 import numpy as np
 
 from flatland.envs.generators import complex_rail_generator
-# from flatland.envs.generators import rail_from_list_of_saved_GridTransitionMap_generator
 from flatland.envs.generators import random_rail_generator
 from flatland.envs.rail_env import RailEnv
 from flatland.utils.rendertools import RenderTool
diff --git a/examples/play_model.py b/examples/play_model.py
index e7447d25c40176eb632763e4ad5ece972d581c45..1cd125b12192236cb9b57ebbdef75e645068357c 100644
--- a/examples/play_model.py
+++ b/examples/play_model.py
@@ -1,7 +1,5 @@
-# import torch
 import random
 import time
-# from flatland.baselines.dueling_double_dqn import Agent
 from collections import deque
 
 import numpy as np
diff --git a/flatland/core/transitions.py b/flatland/core/transitions.py
index c3be1e76baaf54c40d0dfae369e373e2e978c41b..a6d1bb077bdaa0b2c756b5e3f5fc5a35627d2443 100644
--- a/flatland/core/transitions.py
+++ b/flatland/core/transitions.py
@@ -223,7 +223,6 @@ class Grid4Transitions(Transitions):
             (new_transitions[1] & 1) << 2 | \
             (new_transitions[2] & 1) << 1 | \
             (new_transitions[3] & 1)
-        # new_transitions = np.packbits((0, 0, 0, 0) + new_transitions)  # alternative
 
         cell_transition = (cell_transition & negmask) | (new_transitions << ((3 - orientation) * 4))
 
diff --git a/flatland/envs/agent_utils.py b/flatland/envs/agent_utils.py
index 87b7955fb4a5ddd18f5d15ba3d16c5e910e77fdf..8e9ffb99d06176416dfbe2b65bcca09723b1a56c 100644
--- a/flatland/envs/agent_utils.py
+++ b/flatland/envs/agent_utils.py
@@ -4,9 +4,6 @@ import numpy as np
 from attr import attrs, attrib
 
 
-# from flatland.envs.rail_env import RailEnv
-
-
 @attrs
 class EnvDescription(object):
     """ EnvDescription - This is a description of a random env,
diff --git a/flatland/envs/env_utils.py b/flatland/envs/env_utils.py
index 1482b4438bebd82638b873f3232198172a05e6d0..7766363d8482b1c319dd991b93726439cf461f3e 100644
--- a/flatland/envs/env_utils.py
+++ b/flatland/envs/env_utils.py
@@ -8,13 +8,6 @@ a GridTransitionMap object.
 import numpy as np
 
 
-# from flatland.core.env import Environment
-# from flatland.envs.observations import TreeObsForRailEnv
-
-# from flatland.core.transitions import Grid8Transitions, RailEnvTransitions
-# from flatland.core.transition_map import GridTransitionMap
-
-
 def get_direction(pos1, pos2):
     """
     Assumes pos1 and pos2 are adjacent location on grid.
diff --git a/flatland/envs/generators.py b/flatland/envs/generators.py
index eec9a7668ecb190d6389f917532360f0c34b6eb5..040210c484c21ffff1551c394fe5e05051e408f4 100644
--- a/flatland/envs/generators.py
+++ b/flatland/envs/generators.py
@@ -6,10 +6,6 @@ from flatland.envs.env_utils import distance_on_rail, connect_rail, get_directio
 from flatland.envs.env_utils import get_rnd_agents_pos_tgt_dir_on_rail
 
 
-# from flatland.core.env import Environment
-# from flatland.envs.observations import TreeObsForRailEnv
-
-
 def empty_rail_generator():
     """
     Returns a generator which returns an empty rail mail with no agents.
diff --git a/flatland/envs/rail_env.py b/flatland/envs/rail_env.py
index e5a86ca3318f0dbba90cf1998264f9609dee2566..ab019154b8897de142afe3dbe55dd8f0aad8596c 100644
--- a/flatland/envs/rail_env.py
+++ b/flatland/envs/rail_env.py
@@ -5,7 +5,6 @@ Generator functions are functions that take width, height and num_resets as argu
 a GridTransitionMap object.
 """
 # TODO:  _ this is a global method --> utils or remove later
-# from inspect import currentframe
 
 from enum import IntEnum
 
@@ -19,10 +18,6 @@ from flatland.envs.generators import random_rail_generator
 from flatland.envs.observations import TreeObsForRailEnv
 
 
-# from flatland.core.transitions import Grid8Transitions, RailEnvTransitions
-# from flatland.core.transition_map import GridTransitionMap
-
-
 class RailEnvActions(IntEnum):
     DO_NOTHING = 0
     MOVE_LEFT = 1
diff --git a/flatland/utils/editor.py b/flatland/utils/editor.py
index a23bf855a867949f2d15d8bff58d19283a71438f..0ac5bf6a34daa631c1170bf9d50acc402b367fd0 100644
--- a/flatland/utils/editor.py
+++ b/flatland/utils/editor.py
@@ -13,19 +13,10 @@ from examples.play_model import Player
 from flatland.envs.agent_utils import EnvAgent, EnvAgentStatic
 from flatland.envs.env_utils import mirror
 from flatland.envs.generators import complex_rail_generator, empty_rail_generator
-# from flatland.core.transitions import RailEnvTransitions
 from flatland.envs.observations import TreeObsForRailEnv
 from flatland.envs.rail_env import RailEnv, random_rail_generator
 
 
-# from contextlib import redirect_stdout
-# import os
-# import sys
-# import io
-# from PIL import Image
-# from ipywidgets import IntSlider, link, VBox
-
-
 class EditorMVC(object):
     """ EditorMVC - a class to encompass and assemble the Jupyter Editor Model-View-Controller.
     """
diff --git a/flatland/utils/graphics_pil.py b/flatland/utils/graphics_pil.py
index 31c65948750bac9635161ef3cb413fa2d139b868..c00bb1e0ac47c70f012b8b1618a079740a0150c5 100644
--- a/flatland/utils/graphics_pil.py
+++ b/flatland/utils/graphics_pil.py
@@ -1,7 +1,6 @@
 import io
 import os
 import site
-# from flatland.utils.svg import Track, Zug
 import time
 import tkinter as tk
 
@@ -29,7 +28,6 @@ enable_windows_cairo_support()
 from cairosvg import svg2png  # noqa: E402
 from screeninfo import get_monitors  # noqa: E402
 
-# from copy import copy
 from flatland.core.transitions import RailEnvTransitions  # noqa: E402
 
 
diff --git a/flatland/utils/rendertools.py b/flatland/utils/rendertools.py
index 6e6043b511ff6d4054b66c2a9bb8008ae544715e..05e67198389d63f7bfbab432a3e809bcfafbffb6 100644
--- a/flatland/utils/rendertools.py
+++ b/flatland/utils/rendertools.py
@@ -1,7 +1,6 @@
 import time
 from collections import deque
 
-# import xarray as xr
 import numpy as np
 from numpy import array
 from recordtype import recordtype
diff --git a/tests/test_env_edit.py b/tests/test_env_edit.py
index 84531bfa5f96f114415c94d28b9c83c04b41d598..0707cf3ce51c77d9918e25e5b3858a46574b321e 100644
--- a/tests/test_env_edit.py
+++ b/tests/test_env_edit.py
@@ -1,4 +1,3 @@
-# from flatland.envs.agent_utils import EnvAgent
 from flatland.envs.agent_utils import EnvAgentStatic
 from flatland.envs.rail_env import RailEnv
 
diff --git a/tests/test_player.py b/tests/test_player.py
index 75b75c471d0de8bcf401d61e74bfb86c0ce1bb6c..21ff62c32a150391e36a6a38493f05c8d2aa4a00 100644
--- a/tests/test_player.py
+++ b/tests/test_player.py
@@ -1,9 +1,6 @@
 from examples.play_model import main
 
 
-# from examples.tkplay import tkmain
-
-
 def test_main():
     main(render=True, n_steps=20, n_trials=2, sGL="PIL")
     main(render=True, n_steps=20, n_trials=2, sGL="PILSVG")
diff --git a/tests/test_transitions.py b/tests/test_transitions.py
index 86f015f8c800c6d16b5ce4a0827562ad601996cd..41feaab179238a5a9df2b4cdb91fc9feaadfcc2b 100644
--- a/tests/test_transitions.py
+++ b/tests/test_transitions.py
@@ -5,7 +5,6 @@
 import numpy as np
 
 from flatland.core.transitions import RailEnvTransitions, Grid8Transitions
-# from flatland.envs.rail_env import validate_new_transition
 from flatland.envs.env_utils import validate_new_transition