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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 load_text(self, text, tokenizer=None):
 """ Load text from which to generate a word frequency list Args: text (str):
 The text to be loaded tokenizer (function):
 The function to use to tokenize a string """

        if tokenizer:
            words = [x.lower() for x in tokenizer(text)]
        else:
            words = self.tokenize(text)

        self._dictionary.update(words)
        self._update_dictionary()