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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_char_pixels(self, s):
 """ Internal. Safeguards the character indexed dictionary for the show_message function below """


        if len(s) == 1 and s in self._text_dict.keys():
            return list(self._text_dict[s])
        else:
            return list(self._text_dict['?'])