user: Write me a python code that processes a CSV file with the following structure ["Name","URL","Rating"], download each image under the URL row as save as PNG, use the Name as the file name and save it under a subfolder using the Rating as name, add a tkinter GUI to let me choose the CSV file and output path.

assistant: import csv
import requests
import tkinter as tk
from tkinter import filedialog
from tkinter import messagebox

def process_csv(csv_file, output_path):
    with open(csv_file, "r") as file:
        reader = csv.reader(file)
        header = next(reader) # skip the header row
        for row in reader:
            name, url, rating = row
            response = requests.get(url)
            if response.status_code == 200:
                subfolder = output_path + "/" + rating
                if not os.path.exists(subfolder):
                    os.makedirs(subfolder)
                file_path = subfolder + "/" + name + ".png"
                with open(file_path, "wb") as f:
                    f.write(response.content)
            else:
                messagebox.showerror("Error", f"Failed to download {name} from {url}")

def select_csv():
    csv_file = filedialog.askopenfilename(initialdir = "/", title = "Select CSV file", filetypes = (("CSV files", "*.csv"), ("all files", "*.*")))
    if csv_file:
        return csv_file

def select_output_path():
    output_path = filedialog.askdirectory(initialdir = "/", title = "Select output path")
    if output_path:
        return output_path

root = tk.Tk()
root.withdraw()
csv_file = select_csv()
if csv_file:
    output_path = select_output_path()
    if output_path:
        process_csv(csv_file, output_path)
        messagebox.showinfo("Success", "Processing completed")

user: I realized that I actually need to process multiple csvs at once, can you change the code to allow me to do that?

assistant: Sure, I can change the code so that it can process multiple csv files at once.
Here is the altered code:
```
import csv
import requests
import tkinter as tk
from tkinter import filedialog
from tkinter import messagebox
from tkinter import simpledialog

def process_csv(csv_file, output_path):
    with open(csv_file, "r") as file:
        reader = csv.reader(file)
        header = next(reader) # skip the header row
        for row in reader:
            name, url, rating = row
            response = requests.get(url)
            if response.status_code == 200:
                subfolder = output_path + "/" + rating
                if not os.path.exists(subfolder):
                    os.makedirs(subfolder)
                file_path = subfolder + "/" + name + ".png"
                with open(file_path, "wb") as f:
                    f.write(response.content)
            else:
                messagebox.showerror("Error", f"Failed to download {name} from {url}")

def select_csv():
    csv_file = filedialog.askopenfilename(initialdir = "/", title = "Select CSV file", filetypes = (("CSV files", "*.csv"), ("all files", "*.*")))
    if csv_file:
        return csv_file

def select_output_path():
    output_path = filedialog.askdirectory(initialdir = "/", title = "Select output path")
    if output_path:
        return output_path

root = tk.Tk()
root.withdraw()
csv_file_number = simpledialog.askinteger("Number of files to open", "How many files do you want to open?")
for i in range(csv_file_number):
    csv_file = select_csv()
    if csv_file:
        output_path = select_output_path()
        if output_path:
            process_csv(csv_file, output_path)
            messagebox.showinfo("Success", "Processing completed")
```
The new program uses the tkinter library's simpledialog module to ask the user how many files they wish to open, and then it runs the main body of the program that amount of times.