Reconceptualized lab

tile.py

@@ -0,0 +1,43 @@
+from turtle import *
+
+def draw_tile(size):
+    "Draws one tile, which can be repeated to form a pattern."
+    color("grey")
+    square(size)
+    forward(size/2)
+    color("black")
+    left(90)
+    quarter_arc_right(size/4)
+    quarter_arc_left(size/4)
+    quarter_arc_left(size/4)
+    quarter_arc_right(size/4)
+    left(90)
+    fly(size/2)
+    left(90)
+    fly(size)
+    left(90)
+
+def fly(distance):
+    "Moves without drawing."
+    penup()
+    forward(distance)
+    pendown()
+
+def square(size):
+    "Draws a square of side length `size`"
+    forward(size)
+    left(90)
+    forward(size)
+    left(90)
+    forward(size)
+    left(90)
+    forward(size)
+    left(90)
+
+def quarter_arc_right(radius):
+    "Draws a quarter of an arc, turning to the right."
+    circle(-radius, 90)
+
+def quarter_arc_left(radius):
+    "Draws a quarter of an arc, turning to the left."
+    circle(radius, 90)