How can i add a Score in pygame?

import pygame
from pygame.constants import( QUIT, KEYDOWN, KEYUP, K_LEFT, K_RIGHT, K_ESCAPE, K_SPACE, MOUSEBUTTONDOWN)
import os
from random import randint
import time
import sys

class Settings:
    w_width = 800
    w_height = 600
    w_border = 50
    file_path = os.path.dirname(os.path.abspath(__file__))
    image_path = os.path.join(file_path, "pictures")

class Background(object):
    def __init__(self, filename):
        self.imageo = pygame.image.load(os.path.join(Settings.image_path, filename))
        self.image = pygame.transform.scale(self.imageo, (Settings.w_width, Settings.w_height)).convert()
        self.rect = self.image.get_rect()

    def draw(self, screen):
        screen.blit(self.image, self.rect)

Here I already tried to make a the Score class which should creates a font and the score counter.

class Score(object):
    def __init__(self):
        self.black = 0,0,0
        self.count = 0
        self.font = pygame.font.SysFont("comicsans",50, True , True)
        self.text = self.font.render("Score : "+str(self.count),1,self.black)

This funcion should show the Score but im getting an error. TypeError: invalid destination position for blit. And I dont know how to solve this problem

    def show_score(self, screen):
        screen.blit(self.text,100 ,100)

The last Score funcion is to rise the score

    def score_up(self):
        self.count += 1


class Bubble(pygame.sprite.Sprite):
    def __init__(self):
        super().__init__()
        self.width = 50
        self.height = 300
        self.image = pygame.image.load(os.path.join(Settings.image_path, "Blase.png ")).convert_alpha()
        self.image = pygame.transform.scale(self.image, (25, 25))
        self.rect_br = (Settings.w_width//2) + 100, (Settings.w_height//2) + 100
        self.rect = self.image.get_rect()
        self.mousex, self.mousey = pygame.mouse.get_pos()
        self.cx = self.width - 25
        self.cy = self.height - 25
        self.rect.left = randint(Settings.w_border, Settings.w_width - Settings.w_border)
        self.rect.top = randint(Settings.w_border, Settings.w_height - (Settings.w_border * 2))


    def update(self):
        pass

    def scale_up(self):
        self.scale["width"] += 2
        self.scale["height"] += 2

    def scale_down(self):
        self.scale["width"] -= 2
        self.scale["height"] -= 2

    def events(self):
        pass
 
    def draw(self, screen):
        screen.blit(self.image,self.rect )

And here is the Main class where everything happen

    

class Game(object):
    def __init__(self):
        self.screen = pygame.display.set_mode((Settings.w_width, Settings.w_height))
        self.clock = pygame.time.Clock()
        self.runn = False
        self.score = Score()
        self.background = Background("Hintergrund.png")
        self.bubble = pygame.sprite.Group()
        
    
    
    def run(self):
        self.runn = True
        while self.runn:
            self.clock.tick(60)
            self.watch_for_events()
            self.draw()
            self.events()
            
            

    def events(self):
        if len(self.bubble)< 10:
            self.bubble.add(Bubble())
            time.sleep(0.5)
  
    def draw(self):
        self.background.draw(self.screen)
        self.bubble.draw(self.screen)
        self.score.show_score(self.screen)
    
        pygame.display.flip()

    def watch_for_events(self):
        for event in pygame.event.get():
            if event.type == QUIT:
                self.runn = False

            if event.type == MOUSEBUTTONDOWN:
                for bubble in self.bubble:
                    if bubble.rect.collidepoint(event.pos):
                        bubble.kill()
                    
                
if __name__ == '__main__':
    os.environ['SDL_VIDEO_WINDOWS_POS'] = "50, 1100"
    pygame.init()
    game = Game()
    game.run()
    pygame.quit()