import turtle
turtle.forward(180)
turtle.left(90)
turtle.forward(180)
turtle.left(90)
turtle.forward(180)
turtle.left(90)
turtle.forward(180)
turtle.fillcolor('red')
turtle.begin_fill()
turtle.forward(180)
turtle.left(90)
turtle.forward(180)
turtle.left(90)
turtle.forward(180)
turtle.left(90)
turtle.forward(180)

turtle.circle(100)
turtle.end_fill()