Blit is not detecting my Player classes self.pos

Question

My code:

import pgzrun, pgzero, pygame, math, time, random, os
from pgzero.builtins import Actor, animate, keyboard
screen = pgzero.screen.Screen

# screen
WIDTH = 800
HEIGHT = 600

pygame.init()
pygame.mouse.set_visible(False)
os.chdir("c:/Users/carter.breshears/Documents/CSPVSC/Final/Images")
font = pygame.font.Font("Minecraft.ttf", 30)

# player images
playerIdle = pygame.image.load("playerIdle.png")
playerWalkImages = [pygame.image.load("playerRun1.png"), pygame.image.load("playerRun2.png"), pygame.image.load("playerRun3.png"), pygame.image.load("playerRun4.png")]

#variables
    # gameloop
gameover = False



# classes 
class Player:
    def __init__(self, x, y):
        self.x = x
        self.y = y
        self.animationCount = 0
        self.movingRight = False
        self.movingLeft = False
        self.movingUp = False
        self.movingDown = False
    def main(self, screen):
        if self.animationCount + 1 >= 24:
            self.animationCount = 0
        self.animationCount += 1

        if self.movingRight or self.movingUp or self.movingDown:
            screen.blit(pygame.transform.scale(playerWalkImages[self.animationCount//6], (40,74)), (self.x, self.y))
        elif self.movingLeft:
            screen.blit(pygame.transform.scale(pygame.transform.flip(playerWalkImages[self.animationCount//6], True, False), (40,74)), (self.x, self.y))
        else:
            screen.blit(pygame.transform.scale(playerIdle, (40,74)), (self.x, self.y)) ##### This line!
        self.movingRight = False
        self.movingLeft = False
        self.movingUp = False
        self.movingDown = False
        
class PlayerBullet:
    def __init__(self, x, y, mouseX, mouseY):
        self.x = x
        self.y = y
        self.mouseX = mouseX
        self.mouseY = mouseY
        speed = 6
        self.angle = math.atan2(y - mouseY, x - mouseX)
        self.x_vel = math.cos(self.angle) * speed
        self.y_vel = math.sin(self.angle) * speed
    def main(self, screen):
        self.x -= int(self.x_vel)
        self.y -= int(self.y_vel)
        print("bang")

        pygame.draw.circle(screen, "yellow", (self.x+16, self.y+16), 5)

class InvaderEnemy:
    def __init__(self, x, y):
        self.x = x
        self.y = y
        self.greenAnimationImages = [pygame.image.load("virus g.png"), pygame.image.load("virus g2.png")]
        self.yellowAnimationImages = [pygame.image.load("virus y.png"), pygame.image.load("virus y2.png")]
        self.blueAnimationImages = [pygame.image.load("virus b.png"), pygame.image.load("virus b2.png")]
        self.redAnimationImages = [pygame.image.load("virus r.png"), pygame.image.load("virus r2.png")]
        self.animationCount = 0
        self.velocity = 1
        self.lerpFactor = 0.05
        
    def main(self, screen):
        if self.animationCount + 1 == 8:
            self.animationCount = 0
        self.animationCount += 1

        spawnPos = (random.randint(-1000, 1000), random.randint(-1000, 1000))

        targetVector = pygame.math.Vector2(player.x, player.y)
        enemyVector = pygame.math.Vector2(spawnPos.x, spawnPos.y)
        newEnemyVector = pygame.math.Vector2(spawnPos.x, spawnPos.y)

        distance = enemyVector.distance_to(targetVector)
        minDistance = 25
        maxDistance = 1000

        if distance > minDistance:
            directionVector = (targetVector - enemyVector)/2
            self.minStep = max(0, distance - maxDistance)
            self.maxStep = distance - minDistance
            self.stepDistance = self.minStep + (self.maxStep - self.minStep) * self.lerpFactor
            newEnemyVector = enemyVector + directionVector * self.stepDistance

        return(newEnemyVector.x, newEnemyVector.y)

# player
player = Player(400,300)
displayScroll = [0,0]
# shooting
playerBullets = []
# invader
invaders = []
invaderEnemy = InvaderEnemy(100,100) 
invaderSpawnRate = 1

# functions
def update():
    # movement
    keys = pygame.key.get_pressed()
    if keys[pygame.K_a]:
        displayScroll[0] -= 2
        player.movingLeft = True
        for bullet in playerBullets:
            bullet.x += 2

    if keys[pygame.K_d]:
        displayScroll[0] += 2
        player.movingRight = True
        for bullet in playerBullets:
            bullet.x -= 2

    if keys[pygame.K_w]:
        displayScroll[1] -= 2
        player.movingUp = True
        for bullet in playerBullets:
            bullet.y += 2

    if keys[pygame.K_s]:
        displayScroll[1] += 2
        player.movingDown = True
        for bullet in playerBullets:
            bullet.y -= 2

    player.main(screen)

    # shooting
    mouseX, mouseY = pygame.mouse.get_pos()

    for event in pygame.event.get():
        if event.type == pygame.MOUSEBUTTONDOWN:
            if event.button == 1:
                playerBullets.append(PlayerBullet(player.x, player.y, mouseX, mouseY))

    for bullet in playerBullets:
        PlayerBullet.main(screen)
    
    #enemies
    global spawnPos
    if time.perf_counter() - invaderSpawnRate > 1:
        invaders.append(InvaderEnemy(spawnPos.x, spawnPos.y))
    for invader in invaders:
        InvaderEnemy.main(screen)
    


# run
pgzrun.go()

I've tried everything I know of, Im new to this. I know that it worked before because I tested this on my home computer but whenever I downloaded the file on my school computer it stopped working so something must have changed between python versions.