Ckpoint 3 gave explanation for draw_tile_grid

Doc strings are useful becuase they can help you remember what
a block of code does. I think I will use them in the future because
they keep a record of what a block of code does, and can also be used to
refresh your memory on a block of code you had previosuly figured out.

tile.py

@@ -3,22 +3,25 @@ from turtle import *
 def draw_tile(size):
     "Draws one tile, which can be repeated to form a pattern."
     draw_tile_outline(size)
-    draw_squiggle(size)
+    draw_fancysquiggle(size)
 
 def draw_tile_outline(size):
     pencolor("#dddddd")
     square(size)
 
-def draw_squiggle(size):
-    forward(size/4)
-    pencolor("black")
+def draw_fancysquiggle(size):
+    pencolor("blue")
     left(90)
-    quarter_arc_right(size/4)
-    quarter_arc_left(size/4)
-    quarter_arc_left(size/4)
-    quarter_arc_right(size/4)
+    half_arc_right(size/2)
+    left(180)
+    fly(size/2)
     left(90)
-    fly(size/4)
+    fly(size/2)
+    right(90)
+    pencolor("red")
+    forward(size/2)
+    left(90)
+    fly(size/2)
     left(90)
     fly(size)
     left(90)
@@ -35,10 +38,10 @@ def square(size):
         forward(size)
         left(90)
 
-def quarter_arc_right(radius):
-    "Draws a quarter of an arc, turning to the right."
-    circle(-radius, 90)
+def half_arc_right(radius):
+    "Draws a half of an arc, turning to the right."
+    circle(-radius, 180)
 
-def quarter_arc_left(radius):
-    "Draws a quarter of an arc, turning to the left."
-    circle(radius, 90)
+def half_arc_left(radius):
+    "Draws a half of an arc, turning to the left."
+    circle(radius, 180)