Why does is there an error ocurring in my script?

[happy_variable]

It complains about that I didn't define the variable self.lasersOnScreen, what I actually did in the setup of the Main class.

How do I fix it?!

#coding : utf-8

from scene import *
from random import *
from game_menu import ButtonNode
import sound
import random
#This module is not preset, its just the one I'm working on, if you ask what is this.
import _scene_Physics
A = Action

class Powerup(SpriteNode):
    
	def __init__(self, **kwargs):
		SpriteNode.__init__(self, "plf:Item_Star", **kwargs)
		
class Main(Scene):
		
	def shoot(self, type):
		if type == "up":
			self.laser_target_y = get_screen_size()[1]
		if type == "down":
			self.laser_target_y = -768
		if self.powerupActivated == True:
			self.laser_target_y = 768 if type == "up" else -768
		self.la = SpriteNode('spc:LaserGreen12', parent=self)
		self.la.position = self.al.position + (0, 30)
		self.la.z_position = 1
		self.lasersOnScreen.insert(1, self.la)
		actions = [A.move_by(0, self.laser_target_y), A.remove()]
		self.la.run_action(A.sequence(actions))
		self.lasersOnScreen.insert(1, self.la)
		sound.play_effect('digital:Laser4')
	
	def setup(self):
	    _scene_Physics.Gravity.initGravity({"power" : 10})
	    self.powerupActivated = False
	    self.playerLevel = 1
	    self.bricksOnScreen = []
	    self.lasersOnScreen = []
	    self.levelLabel = LabelNode("Level %s" % (self.playerLevel), ("Futura", 20), position=(40, 710), z_position = 1.0, parent=self)
	    self.la = None
	    self.bgimage = SpriteNode("spc:BackgroundPurple", position=(get_screen_size()[0]/2, get_screen_size()[1]/2), size=(get_screen_size()[0], get_screen_size()[1]), parent=self)
	    self.al = SpriteNode("plf:AlienGreen_front", position=(512, 400), parent=self)
	    self.shoot_button = ButtonNode("Shoot", parent=self)
	    self.shoot_button.position = (924, 40)
	    self.obstacleSpawnButton = ButtonNode("Spawn a brick", parent=self)
	    self.upgradeStr = "Upgrade(Cost:100pts)"
	    self.upgradeToNextLevelButton = ButtonNode(self.upgradeStr, parent=self)
	    self.shootDownButton = ButtonNode("Shoot Down", parent=self)
	    self.shootDownButton.position = (924, 100)
	    self.upgradeToNextLevelButton.position = (512, 40)
	    self.obstacleSpawnButton.position = (100, 40)
	    self.score = 0
	    self.scoreLabel = LabelNode(str(self.score), ("Futura", 20), parent=self)
	    self.scoreLabel.position = (40, 740)
	    self.scoreLabel.z_position = 1.0
	    self.shootWith2 = False
	    self.upgradeCost = 100
		
	def touch_ended(self, touch):
		touch_loc = self.point_from_scene(touch.location)
		if touch_loc in self.shoot_button.frame:
			self.shoot(type = "up")
		if touch_loc in self.obstacleSpawnButton.frame:
			o = self.spawn_random_brick()
			self.bricksOnScreen.insert(1, o)
			del o
		if touch_loc in self.upgradeToNextLevelButton.frame:
			if self.score >= self.upgradeCost or self.score == self.upgradeCost:
				self.score -= self.upgradeCost
				self.scoreLabel.text = str(self.score)
				self.playerLevel += 1
		if touch_loc in self.shootDownButton.frame:
			self.shoot(type = "down")
			
	def check_collisions(self):
		if self.lasersOnScreen:
			for brickOnScreen in self.bricksOnScreen:
				for laserOnScreen in self.lasersOnScreen:
					if laserOnScreen.position in brickOnScreen.frame:
						brickOnScreen.run_action(A.remove())
						sound.play_effect(random.choice(["Explosion_1", "Explosion_2", "Explosion_3"]))
						if brickOnScreen in self.bricksOnScreen:
							self.bricksOnScreen.remove(brickOnScreen)
						if random.randint(1, 5) == 4 and self.powerupActivated == False:
							self.pup = Powerup(parent=self)
							self.pup.position = brickOnScreen.position
							actions = [A.move_to(100, 10), A.call(self.powerupActive), A.wait(18), A.call(self.powerupDesactive), A.remove()]
							self.pup.run_action(A.sequence(actions))
						self.score += random.randint(1, 10)
						self.scoreLabel.text = str(self.score)
						if not self.la == None:
							if self.la in self.lasersOnScreen and self.powerupActivated == False:
								self.lasersOnScreen.remove(self.la)
								self.la.run_action(A.remove())
							
	def touch_moved(self, touch):
		touch_loc = self.point_from_scene(touch.location)
		if touch_loc in self.al.frame:
			self.al.position = touch_loc
			
	def spawn_random_brick(self):
		obstacles = ["pzl:Blue8", "pzl:Purple8", "pzl:Yellow4"]
		obstacleName = random.choice(obstacles)
		brick = SpriteNode(obstacleName, position=(random.randint(1, get_screen_size()[0]), random.randint(1, get_screen_size()[1])), parent=self)
		_scene_Physics.Gravity.gravity(_scene_Physics.Gravity(), brick)
		return brick
		
	def update(self):
		self.check_collisions()
		self.levelLabel.text = "Level %s" % (self.playerLevel)
		
	def powerupActive(self):
		self.powerupActivated = True
		
	def powerupDesactive(self):
		self.powerupActivated = False

if __name__ == "__main__":
	run(Main(), LANDSCAPE, show_fps=True)

[omz]

Where exactly do you see this error? I removed the references to the missing _scene_Physics module, and it seemed to work fine.

[abcabc]

Whenever you have "update" method, sometimes the errors are shown at wrong place. You comment out the update method and run the code. Mostly some error would be in setup method. You can enclose "update" method in triple quotes for commenting out and you can remove the quotes after fixing the error.

    """def update(self):
        self.check_collisions()
        self.levelLabel.text = "Level %s" % (self.playerLevel)"""

In your case update method calls check_collisions and in the method the first variable accessed is laserOnScreen. Because of some error setup method may not reach the point to initialize this variable, and hence it may show it as not defined.

[abcabc]

The problem is most likely to be in the following statement

_scene_Physics.Gravity.initGravity({"power" : 10})