app.py

import streamlit as st

A = st.number_input(
    "Insert the initial investment (in $): "
)
r = st.number_input(
    "Insert the interest rate (nominal in %): "
)
T = st.number_input(
    "Insert the number of years of your investment: "
)

y = A * (1 + r/100)**T

st.write(f"Your money after {T} years is ${y}")