Fast script to manually sort many images, but fast (avoid waiting for the image to load slowly)

viewersorter.py

import argparse
from PIL import Image, ImageTk, ImageOps
from os import listdir, path
import tkinter as tk
#from pynput import keyboard # later user event handling and classes

# List all pictures in the directory
# launch viewer on the first
# left right, for previous and next
# up down for ok not ok list, write the list into files to sort

def get_picture_list(path: str) -> list:
    files = listdir(path)
    return sorted(files)

def save_list(file: str, items: list) -> None:
    fd = open(file, 'w+')
    fd.write("\n".join(item for item in items))
    fd.close()

def open_directory(directory: str, output_file: str) -> None:
    pic_list = get_picture_list(directory)
    pic_list_size = len(pic_list)
    pictures_keep = list()
    
    win = tk.Tk()
    win.geometry("800x800")
    
    i=0
    while(i < pic_list_size):
        current_file = path.join(directory, pic_list[i])
        print("Opening: ", current_file)
        print("[ > ]\tN°%d/%d (%d%%)" % (i, pic_list_size, ((i*100)/pic_list_size)))
        
        #loading n showing img
        pic_file = Image.open(current_file)
        pic_file = ImageOps.contain(pic_file, (win.winfo_width(), win.winfo_height()))
        im = ImageTk.PhotoImage(pic_file)
        pane = tk.Label(win, image=im)
        pane.grid(row=0, column=0)
        win.update_idletasks()
        
        #inputing commands
        print(">", end='')
        c = input()
        if(c == 'k'):
            print("+", end='')
            pictures_keep.append(current_file)
        elif(c == 'p'):
            i=i-2
            # if the prev was keept we remove it
            if(path.join(directory, pic_list[i+1]) in pictures_keep):
                pictures_keep.remove(path.join(directory, pic_list[i+1]))
        elif(c == 'q'):
            i = pic_list_size+1
        else:
            print("-", end='')
        i+=1
        
    print("[ < ]\tOK")
    if(output_file != None):
        save_list(output_file, pictures_keep)
    print("Files to keep ({} of {}):\n".format(len(pictures_keep), pic_list_size), pictures_keep)

if __name__ == "__main__":
    parser = argparse.ArgumentParser(prog="picsort", description="sort pictures")
    parser.add_argument('-d', '--directory', type=str, help="Directory to load and sort", required=True)
    parser.add_argument('-o', '--output', type=str, help="List of files to keep", required=False)

    args = parser.parse_args()
    
    print("Welcome to pic sorter\nUsage:\n\tn\tnext\n\tk\tkeep\n\tj\tdelete")
    open_directory(args.directory, args.output)