paises.py

#!/usr/bin/env python3

#lista de paises
paises = ["Argentina", "Brasil", "Chile", "Uruguay"]

#actualizo tercer elemento
paises[2] = "Perú"

#Agrego un pais
# a continuacion se concatenan dos listas
output = paises + ["Paraguay", "Ecuador"]

# Unimos  3 listas
output2 = [ "mexico", "honduras"] + paises + ["Paraguay", "Ecuador"]

#imprime
print(output)
print(output2)