Colliderect function not working in Pygame - oop

Question

So I am making a pong game in pygame while implementing oop. My problem is the colliderect function is giving me the error " ball_hitter object has no attribute 'colliderect'". I've used the colliderect function before but it's not working for me this time.
Code:
import pygame
from pygame.locals import *
pygame.init()
screen = pygame.display.set_mode((500,500))
pygame.display.set_caption("Pong With Classes!")
#Variables
red = (255,0,0)
blue = (0,0,255)
black = (0,0,0)
clock = pygame.time.Clock()
#End of Variables
class ball_hitter:
def __init__(self,x,y,length,width,color):
self.x = x
self.y = y
self.length = length
self.width = width
self.color = color
self.left = False
self.right = False
def draw_ball_hitter(self):
screen.fill(black)
pygame.draw.rect(screen,self.color,(self.x,self.y,self.length,self.width))
#Paddle creation
paddle = ball_hitter(250,400,130,20,red)
#End of Paddle Creation
class thing_thats_being_hit:
def __init__(self,x,y,color):
self.x = x
self.y = y
self.radius = 27
self.color = color
self.speed_x = -4
self.speed_y = 4
def draw_googlyball(self):
pygame.draw.circle(screen,self.color,(self.x,self.y),self.radius)
def move(self):
self.x += self.speed_x
self.y += self.speed_y
#Ball Creation
ball = thing_thats_being_hit(200,50,blue)
#End of Ball Creation
#Paddle Collision
if paddle.colliderect(ball):
print("It Worked!")
#End Of Paddle Collision
ball.move()
while True:
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
exit()
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_LEFT:
paddle.left = True
if event.key == pygame.K_RIGHT:
paddle.right = True
if event.type == pygame.KEYUP:
if event.key == pygame.K_LEFT:
paddle.left = False
if event.type == pygame.KEYUP:
if event.key == pygame.K_RIGHT:
paddle.right = False
paddle.draw_ball_hitter()
ball.draw_googlyball()
if paddle.left == True:
paddle.x = paddle.x - 2
if paddle.right == True:
paddle.x = paddle.x + 2
if ball.x <= 0:
ball.speed_x*=-1
if ball.x >= 500:
ball.speed_x *= -1
if ball.y >= 500:
pygame.quit()
ball.move()
pygame.display.update()
clock.tick(100)
I would appreciate it if someone could give me a fixed code and explain is to me.

Answer 1

See How do I detect collision in pygame?. colliderect is a method of pygame.Rect. Therefore you need to create pygame.Rect objects. Also you have to do the collision test in the application loop instead of before the application loop:
while True:
# [...]
paddle_rect = pygame.Rect(paddle.x, paddle.y, paddle.width, paddle. length)
ball_rect = pygame.Rect(ball.x - ball.radius, ball.y - ball.radius,
ball.radius * 2, ball.radius * 2)
if paddle_rect.colliderect(ball_rect):
print("It Worked!")