Why Won't My shape Show Up in the Turtle Module

Two problems:

1. Some settings are initialized and the pen is lifted up but the paddle turtle never draws anything. So there's nothing to see. Try calling a drawing function like .stamp() to print something.

   Also, as a general note, make sure your turtle's location is within the window bounds when you do draw with it, although x at -350 should be fine here.

2. The main turtle loop is never run. This builds the window and blocks the script from exiting until the window is closed. I usually use turtle.exitonclick() but something like turtle.mainloop() also works. This belongs at the end of the main code, although some platforms run the loop automatically.

import turtle

wm = turtle.Screen()
wm.title("Pong by Zachary Bye")
wm.bgcolor("black")
wm.setup(width=800, height=600)
wm.tracer(0)


#Paddle a
paddle_a = turtle.Turtle()
paddle_a.speed(0)
paddle_a.shape("square")
paddle_a.color("white")
paddle_a.shapesize # this line does nothing
paddle_a.penup()
paddle_a.goto(-350,0)
paddle_a.stamp() # draw something
turtle.exitonclick() # run the main turtle loop

when I create the paddle, it won't show up.

The reason is you invoked tracer(0) which says, "don't draw anything until I explicitly call update(). And then you didn't call update()! This is how I would write your code fragment:

from turtle import Screen, Turtle

screen = Screen()
screen.title("Pong by Zachary Bye")
screen.setup(width=800, height=600)
screen.bgcolor('black')
screen.tracer(0)

# Paddle a
paddle_a = Turtle()
paddle_a.shape('square')
paddle_a.color('white')
paddle_a.shapesize(5, 1)
paddle_a.penup()
paddle_a.setx(-350)

screen.update()
screen.mainloop()

My general rule is to avoid tracer() and update() until your code is basically working and you want to optimize the graphics.