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)

def draw_tile_outline(size):
    pencolor("#dddddd")
    square(size)

def draw_squiggle(size):
    forward(size/25)
    pencolor("pink")
    left(135)
    half_arc_right(size * 2)
    half_arc_left(size * 2)
    half_arc_left(size * 2)
    half_arc_right(size * 2)
    left(135)
    fly(size/2)
    left(135)
    fly(size/2)
    left(135)

def fly(distance):
    "Moves without drawing."
    penup()
    forward(distance)
    pendown()

def square(size):
    "Draws a square of side length `size`"
    for side in range(9):
        forward(size)
        left(135)

def half_arc_right(radius):
    "Draws a quarter of an arc, turning to the right."
    circle(-radius, 180)

def half_arc_left(radius):
    "Draws a quarter of an arc, turning to the left."
    circle(radius, 180)