Python List: Digital Braille

I am making a function that translates normal strings into Braille characters.
To make the Braille dictionary, I create an empty braille_dictionary dictionary and then 2 functions addNumbers() and addLetters() to add keys and values to that dictionary:

def addNumbers(bd):
    bd['1'] = [1, 0, 0, 0, 0, 0]
    bd['2'] = [1, 1, 0, 0, 0, 0]
    bd['3'] = [1, 0, 0, 1, 0, 0]
    bd['4'] = [1, 0, 0, 1, 1, 0]
    bd['5'] = [1, 0, 0, 0, 1, 0]
    bd['6'] = [1, 1, 0, 1, 0, 0]
    bd['7'] = [1, 1, 0, 1, 1, 0]
    bd['8'] = [1, 1, 0, 0, 1, 0]
    bd['9'] = [0, 1, 0, 1, 0, 0]
    bd['0'] = [0, 1, 0, 1, 1, 0]


def addLetters(bd):
    bd['a'] = [1, 0, 0, 0, 0, 0]
    bd['b'] = [1, 1, 0, 0, 0, 0]
    bd['c'] = [1, 0, 0, 1, 0, 0]
    bd['d'] = [1, 0, 0, 1, 1, 0]
    bd['e'] = [1, 0, 0, 0, 1, 0]
    bd['f'] = [1, 1, 0, 1, 0, 0]
    bd['g'] = [1, 1, 0, 1, 1, 0]
    bd['h'] = [1, 1, 0, 0, 1, 0]
    bd['i'] = [0, 1, 0, 1, 0, 0]
    bd['j'] = [0, 1, 0, 1, 1, 0]

    bd['k'] = [1, 0, 1, 0, 0, 0]
    bd['l'] = [1, 1, 1, 0, 0, 0]
    bd['m'] = [1, 0, 1, 1, 0, 0]
    bd['n'] = [1, 0, 1, 1, 1, 0]
    bd['o'] = [1, 0, 1, 0, 1, 0]
    bd['p'] = [1, 1, 1, 1, 0, 0]
    bd['q'] = [1, 1, 1, 1, 1, 0]
    bd['r'] = [1, 1, 1, 0, 1, 0]
    bd['s'] = [0, 1, 1, 1, 0, 0]
    bd['t'] = [0, 1, 1, 1, 1, 0]

    bd['u'] = [1, 0, 1, 0, 0, 1]
    bd['v'] = [1, 1, 1, 0, 0, 1]
    bd['x'] = [1, 0, 1, 1, 0, 1]
    bd['y'] = [1, 0, 1, 1, 1, 1]
    bd['z'] = [1, 0, 1, 0, 1, 1]
    bd['w'] = [0, 1, 0, 1, 1, 1]

Here is my translator function:

def translator(string,braille_dict):
    stringList = []
    characterList = []
    wordList = string.lower().split()
    for i in wordList:
        if i.lower() in braille_dict:
            i = braille_dict[i]
            characterList.append(i)
        if i.lower() not in braille_dict:
            for j in i:
                if j in braille_dict:
                 j = braille_dict[j]
                 characterList.append(j)
                if j not in braille_dict:
                 j = []
                 translated.append(j)
   stringList.append(characterList)
    return stringList

The problem is that, I want the list characterList to store each single word. For example, if I want to translate the sentence “Hello it’s me”, “Hello” characters should be in one list, then that list is nested in the stringList. But my function cannot put “Hello” in a sublist; it’s just comprised of every single character in the whole sentence.

To be more specific, I want to return “Hello it’s me” as [[Hello], it’s, me] but my code is returning [Hello, it’s, me] instead.

Is there any way to solve this?