how to solve (-215:Assertion failed) !empty() in function 'cv::CascadeClassifier::detectMultiScale'

edit

please help me i got this error.

error                                     Traceback (most recent call last)
<ipython-input-27-8f798bcb3e24> in <module>
     19 
     20     rerect_size = cv2.resize(im, (im.shape[1] // rect_size, im.shape[0] // rect_size))
---> 21     faces = haarcascade.detectMultiScale(rerect_size)
     22     for f in faces:
     23         (x, y, w, h) = [v * rect_size for v in f]

error: OpenCV(4.4.0) C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-9d_dfo3_\opencv\modules\objdetect\src\cascadedetect.cpp:1689: error: (-215:Assertion failed) !empty() in function 'cv::CascadeClassifier::detectMultiScale'

this is my code

import cv2
import numpy as np
from tensorflow.keras.models import load_model
model=load_model("E:\Data Science\Mask detector\model2-008.model")

results={0:'without mask',1:'mask'}
GR_dict={0:(0,0,255),1:(0,255,0)}

rect_size = 4
cap = cv2.VideoCapture(0) 


haarcascade = cv2.CascadeClassifier('/home/user_name/.local/lib/python3.6/site-packages/cv2/data/haarcascade_frontalface_default.xml')

while True:
    (rval, im) = cap.read()
    im=cv2.flip(im,1,1) 


    rerect_size = cv2.resize(im, (im.shape[1] // rect_size, im.shape[0] // rect_size))
    faces = haarcascade.detectMultiScale(rerect_size)
    for f in faces:
        (x, y, w, h) = [v * rect_size for v in f] 

        face_img = im[y:y+h, x:x+w]
        rerect_sized=cv2.resize(face_img,(150,150))
        normalized=rerect_sized/255.0
        reshaped=np.reshape(normalized,(1,150,150,3))
        reshaped = np.vstack([reshaped])
        result=model.predict(reshaped)


        label=np.argmax(result,axis=1)[0]

        cv2.rectangle(im,(x,y),(x+w,y+h),GR_dict[label],2)
        cv2.rectangle(im,(x,y-40),(x+w,y),GR_dict[label],-1)
        cv2.putText(im, results[label], (x, y-10),cv2.FONT_HERSHEY_SIMPLEX,0.8,(255,255,255),2)

    cv2.imshow('LIVE',   im)
    key = cv2.waitKey(10)

    if key == 27: 
        break

cap.release()

cv2.destroyAllWindows()