boneco = "ola. eu sou o joao."
def ponto(texto):
nova = ""
l=len(texto)
for i in range(0,l):
if i==l-1:
nova+=texto[i]
return nova
if texto[i-2]=='.' and i>=2:
a = texto[i].upper()
nova+=a
else:
nova=nova+texto[i]
return nova
print (ponto(boneco))
Ym9uZWNvID0gIm9sYS4gZXUgc291IG8gam9hby4iCgpkZWYgcG9udG8odGV4dG8pOgoJbm92YSA9ICIiCglsPWxlbih0ZXh0bykKCWZvciBpIGluIHJhbmdlKDAsbCk6CgkJaWYgaT09bC0xOgoJCQlub3ZhKz10ZXh0b1tpXQoJCQlyZXR1cm4gbm92YSAKCQlpZiB0ZXh0b1tpLTJdPT0nLicgYW5kIGk+PTI6CQoJCQlhID0gdGV4dG9baV0udXBwZXIoKQoJCQlub3ZhKz1hCgkJZWxzZTogCgkJCW5vdmE9bm92YSt0ZXh0b1tpXQoJcmV0dXJuIG5vdmEKCnByaW50IChwb250byhib25lY28pKQ==