Text not displaying - Python (PyGame)

In your current code, this line is the problem: text.blit(text, (self.x, self.y)). This code is drawing some text onto itself. You want to draw the text onto the screen. Replace that line with this line: screen.blit(text, (self.x, self.y)). This means that you need to have a screen argument for your Text's draw function. So def draw(self): should be def draw(self,screen):. Finally, you must pass the self.screen argument, so self.p1Score.draw() should be self.p1Score.draw(self.screen). The final code, with all changes made should be:

class Player(pygame.sprite.Sprite):
    def __init__(self, x, color):
        pygame.sprite.Sprite.__init__(self)

        self.image = pygame.Surface((10, 100))
        self.image.fill(color)
        self.rect = self.image.get_rect()
        self.rect.y = HEIGHT / 2 - self.rect.height / 2
        self.rect.centerx = x
        self.displacement = 8
        self.score = 0

    def update(self):
        # update function

        self.constrain(0, HEIGHT - self.rect.height)

    def constrain(self, min, max):
        # constrian player to walls

        if self.rect.y > max:
            self.rect.y = max
        if self.rect.y < min:
            self.rect.y = min


class Text():
    def __init__(self, x, y, color, text, font):
        self.x = x
        self.y = y
        self.color = color
        self.text = text
        self.font = font

    def draw(self,screen):
        text = self.font.render(self.text, False, self.color)
        screen.blit(text, (self.x, self.y))

class Game(pygame.sprite.Sprite):
    def __init__(self):
        # get sprite object
        pygame.sprite.Sprite.__init__(self)

        # init pygame
        pygame.init()

        # init pygame modules
        pygame.mixer.init()
        pygame.font.init()

        # set window
        self.screen = pygame.display.set_mode((WIDTH, HEIGHT))
        # set title
        pygame.display.set_caption(TITLE)
        # holds whether the game is running for not
        self.running = True
        # get timer function
        self.clock = pygame.time.Clock()

        # set fonts
        self.scoreText = pygame.font.Font("assets/fonts/square.TTF", 25)
        self.titleFontLight = pygame.font.Font("assets/fonts/square.TTF", 50)

        # group for sprites
        self.allSprites = pygame.sprite.Group()

    def new(self):
        # creates a new game

        # make players
        self.player1 = Player(20, RED)
        self.player2 = Player(WIDTH - 30, BLUE)
        self.ball = Ball()
        self.p1Score = Text(100, 100, (RED), str(self.player1.score), self.scoreText)
        self.p2Score = Text(WIDTH - 10, 10, (WHITE), str(self.player2.score), self.scoreText)

        # put players inside groups
        self.allSprites.add(self.player1)
        self.allSprites.add(self.player2)

        # run game loop
        self.gameLoop()

    def gameLoop(self):
        # main game loop

        while self.running:
            self.allSprites.update()
            self.update()
            self.clock.tick(FPS)

    def update(self):
        # updates game

        self.draw()

        pygame.display.update()

    def draw(self):
        # draws to screen

        # set background color
        self.screen.fill(BLACK)

        # draw to screen
        self.ball.draw(self.screen)
        self.p1Score.draw(self.screen)
        self.allSprites.draw(self.screen)

if __name__ == '__main__':
    Game().new()