Python - Funcion con palabras

def acronWord(word, delimiter = False):

    if (isinstance(word, str)):

        acron = ""

        arr_word =  word.split(delimiter.strip()) if (delimiter and isinstance(delimiter, str)) else word.split()

        for i in arr_word:

            acron += (i.strip())[0].upper()

        return acron

    else:

        return "El valor %s no es una cadena" % word

print acronWord("Alta:velocidad:Espana", ":") # imprime AVE

print acronWord("Alta Velocidad Espana") # imprime AVE

def acronWord(word, delimiter = False):

    if (isinstance(word, str)):

        acron = ""

        arr_word =  word.split(delimiter.strip()) if (delimiter and isinstance(delimiter, str)) else word.split()

        for i in arr_word:

            acron += (i.strip())[0].upper()

        return acron

    else:

        return "El valor %s no es una cadena" % word

print (acronWord(input("Ingrese la palabra: "), input("Ingrese el delimitador (enter para pasarlo por alto): ")))