draw_box.py

def draw_box(image_path, cor, thickness=3): 
    pts=[]  
    x_coordinates=cor[0][0]
    y_coordinates=cor[0][1]
    # store the top-left, top-right, bottom-left, bottom-right 
    # of the plate license respectively
    for i in range(4):
        pts.append([int(x_coordinates[i]),int(y_coordinates[i])])
    
    pts = np.array(pts, np.int32)
    pts = pts.reshape((-1,1,2))
    vehicle_image = preprocess_image(image_path)
    
    cv2.polylines(vehicle_image,[pts],True,(0,255,0),thickness)
    return vehicle_image

plt.figure(figsize=(8,8))
plt.axis(False)
plt.imshow(draw_box(test_image,cor))