Why does my code keep quitting when i open it? *IN PYGAME*

Question

below is my code for a game I am trying to make in pygame. I am trying to run it to test it out, but whenever I press the play game button it quits on me. It's weird and I tried checking maybe I was doing something wrong in the game function, but I could not seem to find anything. I opened the rules, and the rules seem to work perfectly fine, so does the quit game button. Why is this happening with the play game button, am I missing something?

# the following code will always put the screen in the top corner
import os
os.environ['SDL_VIDEO_WINDOW_POS'] = "%d, %d" %(20, 20)
import random
from pygame import * 
init()
size = width, height = 1000, 700
screen = display.set_mode(size)

#define colours
black = (0, 0, 0)
white = (255, 255, 255)
blue = (0, 0, 255)
green = (0, 255, 0)
red = (255, 0, 0)
pink = (255, 192, 203)
light_pink = (255, 183, 193)
light_pink2 = (255, 192, 203)
hot_pink = (255, 105, 180)
peachpuff = (255, 218, 185)
violet = (199, 21, 133)
scoreboard = (128, 71, 3)

# define fonts
menuFont = font.SysFont("Times New Roman",60)

#states in the Game
STATE_MENU = 0
STATE_GAME = 1
STATE_RULES = 2
STATE_QUIT = 3
player = []
playerMove = 2


def drawMenu(screen, button, mx, my, state):
    global player
    blockWidth = width//3
    blockHeight = height//7    
    rectList = [Rect(blockWidth, blockHeight, blockWidth, blockHeight), # game choice
                Rect(blockWidth, 3*blockHeight, blockWidth, blockHeight), #help choice
                Rect(blockWidth, 5*blockHeight, blockWidth, blockHeight)] # quite choice
    stateList = [STATE_GAME, STATE_RULES, STATE_QUIT]
    titleList = ["Play Game", "Rules", "Quit Game"]
    draw.rect(screen, peachpuff, (0, 0, width, height))
    
    for i in range(len(rectList)):
        rect = rectList[i] # get the current Rect
        draw.rect(screen, violet, rect)  # draw the Rect
        text = menuFont.render(titleList[i] , 1, black) # make the font`
        textWidth, textHeight = menuFont.size(titleList[i]) # get the font size
        useW = (blockWidth - textWidth)//2  #use for centering
        useH = (blockHeight - textHeight)//2
        # getting a centered Rectangle
        textRect = Rect(rect[0] + useW, rect[1] + useH, textWidth, textHeight)
        screen.blit(text, textRect) # draw to screen
        
        if rect.collidepoint(mx, my):
            draw.rect(screen, black, rect, 2)
            if button == 1:
                state = stateList[i]
                if STATE_GAME: 
                    player = [random.randint(10, width + 10), random.randint(height//5 - 10, height + 10)]
                    
    return state

def drawScoreboard(screen, mx, my, button): 
    #drawing the score board
    scoreboardHeight, scoreboardWidth = height/5, width/6
    draw.rect(screen, scoreboard, (0, 0, width, scoreboardHeight))
    draw.rect(screen, black, (0, 0, width, scoreboardHeight), 3) 
    string = "Welcome to your first day as a garbage collector!"
    text = menuFont.render(string, 0, red)
    screen.blit(text, Rect(10, 500, 500, 500))
    backRect = Rect((0, 0, width//15, scoreboardHeight//3))
    draw.rect(screen, green, backRect)
    
    #if the ball collides with the back button it will either bold itself 
    #or else it will just have a 1 pixel rect around
    if backRect.collidepoint(mx, my):
        draw.rect(screen, black, backRect, 3)
        if button == 1:
            return STATE_MENU
    else:
        draw.rect(screen, black, backRect, 1)


    
def drawGame(screen, button, mx, my, state):
    global player
    scoreboardHeight = height //5
    draw.rect(screen, blue, (0, 0, width, height))
    draw.rect(screen, black, (0, 0, width, height), 2)
    state = drawScoreboard(screen, mx, my, button)
    #character drawing
    draw.circle(screen, light_pink2, player, 10) 
    draw.circle(screen, black, player, 12, 1) 
    
    
    if button == 3:
        state = STATE_MENU
    
    if mx < player[0] and mx >= 10 + playerMove:
        player[0] -= playerMove
      
        
    if my < player[1] and my >= scoreboardHeight + 10:
        player[1] -= playerMove
        
    if mx > player[0] and mx <= width - 10:
        player[0] += playerMove
    
    if my > player[1] and mx <= height + 10:
        player[1] += playerMove
   
    return state
    
def drawRules(screen, button, mx, my, state):      
    draw.rect(screen, pink, (0, 0, width, height))
    string = "Hi there!" 
    text = menuFont.render(string, 0, red)
    screen.blit(text, Rect(430, 100, 500, 500)) 
    if button == 3:
        state = STATE_MENU
    return state

running = True
#myClock = time.Clock()
# initializing variables
state = STATE_MENU
mx = my = 0

# Game Loop
while running:
    button = 0
    for e in event.get():             # checks all events that happen
        if e.type == QUIT:
            running = False
        if e.type == MOUSEBUTTONDOWN:
            mx, my = e.pos          
            button = e.button
        elif e.type == MOUSEMOTION:
            mx, my = e.pos          
            #button = e.button 
            
    if state == STATE_MENU:                
        state = drawMenu(screen, button, mx, my, state)
    elif state == STATE_GAME:
        state = drawGame(screen, button, mx, my, state)
    elif state == STATE_RULES:
        state = drawRules(screen, button, mx, my, state)
    else:
        running = False
        
    display.flip()

#myClock.tick(60) # waits long enough to have 60 fps
event.get()  
quit()

Thanks a lot for helping out!

Answer 1

In drawGame:

def drawGame(screen, button, mx, my, state):
    global player
    scoreboardHeight = height // 5
    draw.rect(screen, blue, (0, 0, width, height))
    draw.rect(screen, black, (0, 0, width, height), 2)
    state = drawScoreboard(screen, mx, my, button)  # reassignment
    # character drawing
    draw.circle(screen, light_pink2, player, 10)
    draw.circle(screen, black, player, 12, 1)

This marked 'state' reassignment shadows function argument 'state', to a result of drawScoreboard.

in drawScoreboard:

if backRect.collidepoint(mx, my):
    draw.rect(screen, black, backRect, 3)
    if button == 1:
        return STATE_MENU   # << only returns here
else:
    draw.rect(screen, black, backRect, 1)

On this block, it only returns value in certain divergence. Therefore you get None at other cases, and this escapes Game loop block's if-elif chain and go to else, set 'running' to false.

On Game loop Block:

if state == STATE_MENU:
    state = drawMenu(screen, button, mx, my, state)
elif state == STATE_GAME:
    state = drawGame(screen, button, mx, my, state)
elif state == STATE_RULES:
    state = drawRules(screen, button, mx, my, state)
else:
    running = False  # << state = None goes here.

If you put print(state) just before 'if state == STATE_MENU:', you get following result that might help you debugging your game.

lots of zeros...
0
0
0
0
1
None

Process finished with exit code -1

Answer 2

In your function drawGame, you have:

state = drawScoreboard(screen, mx, my, button)

You accidentally redefined state with the scoreboard. Use the following code for the drawGame function and your game should run as expected.

def drawGame(screen, button, mx, my, state):
    global player
    scoreboardHeight = height //5
    draw.rect(screen, blue, (0, 0, width, height))
    draw.rect(screen, black, (0, 0, width, height), 2)
    drawScoreboard(screen, mx, my, button)
    #character drawing
    draw.circle(screen, light_pink2, player, 10) 
    draw.circle(screen, black, player, 12, 1)