Thanks so much. It works perfectly.

Yay! I finally figured out how to get the ship to wrap around. Now I need to figure out how to detect collisions...

from scene import *

class MyScene (Scene):
def bad_guy(self):
self.badGuy.run_action(Action.repeat(Action.sequence(Action.move_by(-818, 0, 5), Action.move_by(818, 0, 0.001)), -1))

def setup(self):
    self.background_color = 'midnightblue'
    self.ship = SpriteNode('spc:PlayerShip1Orange')
    self.ship.position = self.size/2
    self.add_child(self.ship)
    self.badGuy = SpriteNode('spc:EnemyBlack4')
    self.bx,self. by = self.size
    self.by -= 50
    self.bx += 50
    self.badGuy.position = (self.bx, self.by)
    self.add_child(self.badGuy)
    self.bad_guy()
    
def update(self):
    x,y,z = gravity()
    pos = self.ship.position
    pos += (x * 15, y * 15)
    pos.x = max(0, min(self.size.w, pos.x))
    pos.y = max(0, min(self.size.h, pos.y))
    self.ship.position = pos
    
def touch_began(self, touch):
    laser = SpriteNode('spc:LaserBlue9', position=self.ship.position, z_position=-1, parent=self)
    laser.run_action(Action.sequence(Action.move_by(0,1000), Action.remove()))

run(MyScene(), PORTRAIT)

I made your changes, you're right, I'm not getting anymore errors but still am not able to get it to wrap around. I think maybe I could use another action.move_to() with a timing mode that will get it there instantly, so no one could see it but I'm not sure where to find documentation on the different timing modes. Any help?

from scene import *

class MyScene (Scene):
def setup(self):
self.background_color = 'midnightblue'
self.ship = SpriteNode('spc:PlayerShip1Orange')
self.ship.position = self.size/2
self.add_child(self.ship)
self.badGuy = SpriteNode('spc:EnemyBlack4')
self.bx,self. by = self.size
self.by -= 50
self.bx += 50
self.badGuy.position = (self.bx, self.by)
self.add_child(self.badGuy)

def update(self):
    x,y,z = gravity()
    pos = self.ship.position
    pos += (x * 15, y * 15)
    pos.x = max(0, min(self.size.w, pos.x))
    pos.y = max(0, min(self.size.h, pos.y))
    self.ship.position = pos
    
def resetBad(self):
        self.badGuy.position = (self.bx, self.by)
    
def touch_began(self, touch):
    resetBadGuy = Action.call(self.resetBad)
    laser = SpriteNode('spc:LaserBlue9', position=self.ship.position, z_position=-1, parent=self)
    laser.run_action(Action.sequence(Action.move_by(0,1000), Action.remove()))
    self.badGuy.run_action(Action.repeat(Action.sequence(Action.move_by(-818, 0, 5), self.resetBad), -1))
    print self.badGuy.position.x
    #self.badGuy.position = (self.bx, self.by)

run(MyScene(), PORTRAIT)

I'm working on a space shooter game and I can't figure out how to get the 'enemy' spaceship to wrap around to the other side of the screen. Here's my code so far. Hope someone can give some suggestions.

from scene import *

class MyScene (Scene):
    def setup(self):
        self.background_color = 'midnightblue'
        self.ship = SpriteNode('spc:PlayerShip1Orange')
        self.ship.position = self.size/2
        self.add_child(self.ship)
        self.badGuy = SpriteNode('spc:EnemyBlack4')
        self.bx,self. by = self.size
        self.by -= 50
        self.bx += 50
        self.badGuy.position = (self.bx, self.by)
        self.add_child(self.badGuy)
        
    def update(self):
        x,y,z = gravity()
        pos = self.ship.position
        pos += (x * 15, y * 15)
        pos.x = max(0, min(self.size.w, pos.x))
        pos.y = max(0, min(self.size.h, pos.y))
        self.ship.position = pos
        
    def resetBad(self):
            self.badGuy.position = (self.bx, self.by)
        
    def touch_began(self, touch):
        resetBadGuy = Action.call(self.resetBad())
        laser = SpriteNode('spc:LaserBlue9', position=self.ship.position, z_position=-1, parent=self)
        laser.run_action(Action.sequence(Action.move_by(0,1000), Action.remove()))
        self.badGuy.run_action(Action.repeat(Action.sequence(Action.move_by(-818, 0, 5), resetBad), -1))
        print self.badGuy.position.x
        #self.badGuy.position = (self.bx, self.by)
        
    
        
run(MyScene(), PORTRAIT)