app.py

import streamlit as st
import numpy as np

st.title("Todo List")

def add_task():
 task = st.text_input('Add a new task:')
 if st.button('Add'):
    if task:
      tasks.append(task)
 return st.write('Tasks:', tasks)

def check_task():
 task = st.selectbox('Select a task to check:', tasks)
 if st.button('Check'):
    tasks.remove(task)
    checked.append(task)
 return st.write('Checked:', checked)

def reset_task():
 st.button('Reset').click(reset_tasks)

def reset_tasks():
 tasks[:] = []
 checked[:] = []

tasks = []
checked = []

add_task()

if st.checkbox('Check', checked):
 check_task()

reset_task()