Python Turtle Code: Helix

An image of a helix generated by spindles with lengths that depend on the sines of changing angle measurements. The Python math module is necessary in the code.

Please feel free to copy and paste the Python Turtle code that is given here. (Caution please: I had to remove the "less than" or "greater than" symbols in two lines below because Youtube does not allow them in the Description)

Enjoy anyway!
import turtle
import math #math module is needed for sine and pi
scrin = turtle.Screen()
scrin.bgcolor("yellow")
t = turtle.Turtle()
t.hideturtle()
t.pensize(3)
t.speed(0)
x = -500 #helix is generated on left of screen: (-500, 0)
a = 0
y = 0
for i in range(49): #49 spindles on a twisted helix
t.penup()
sin = math.sin(a) #spindle length is 220 * sin a
if -.002 = sin = .002: #Please edit this line because Youtube does not allow "less than" or "greater than" symbols. Please refer to the code in video.
len = 0
t.goto(x, -10) #if spindle length is 0, the circle with r = 10 at spindle end is at (x, -10)
t.pendown()
t.color("blue")
t.circle(10)
y = 0 #y is reset to 0 after drawing circle at (x, -10)
else:
if sin 0: #Please edit this line because Youtube does not allow "less than" or "greater than" symbols. Please refer to the code in video.
len = 220 * sin + 10
t.goto(x, y)
t.left(90)
t.pendown()
t.color("red")
t.forward(len)
t.left(90)
t.color("blue")
t.circle(10)
t.left(180)
else:
len = 220 * sin - 10
t.goto(x, y)
t.left(90)
t.pendown()
t.color("red")
t.forward(len)
t.right(90)
t.color("blue")
t.circle(10)
x += 1000/48 #x value increases by 1000/48 after every loop iteration; 48 spindles after first
a += 4 * math.pi / 48 #angle a increases in 4 * math.pi / 48 every loop iteration
scrin.exitonclick()