cleanup flake8

examples/tkplay.py

-
+import time
 import tkinter as tk
+
 from PIL import ImageTk, Image
+
 from examples.play_model import Player
-from flatland.envs.rail_env import RailEnv
 from flatland.envs.generators import complex_rail_generator
+from flatland.envs.rail_env import RailEnv
 from flatland.utils.rendertools import RenderTool
-import time
 
 
 def tkmain(n_trials=2):
@@ -36,14 +37,14 @@ def tkmain(n_trials=2):
         for step in range(n_steps):
             oPlayer.step()
             env_renderer.renderEnv(show=True, frames=True, iEpisode=trials, iStep=step,
-                action_dict=oPlayer.action_dict)
+                                   action_dict=oPlayer.action_dict)
             img = env_renderer.getImage()
             img = Image.fromarray(img)
             tkimg = ImageTk.PhotoImage(img)
 
             if first:
-                panel = tk.Label(window, image = tkimg)
-                panel.pack(side = "bottom", fill = "both", expand = "yes")
+                panel = tk.Label(window, image=tkimg)
+                panel.pack(side="bottom", fill="both", expand="yes")
             else:
                 # update the image in situ
                 panel.configure(image=tkimg)
@@ -56,4 +57,4 @@ def tkmain(n_trials=2):
 
 
 if __name__ == "__main__":
-    tkmain()
\ No newline at end of file
+    tkmain()