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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 _update_hash(self, arg):
 """ Takes an argument and updates the hash. The argument can be an np.array, string, or list of things that are convertable to strings. """

        if isinstance(arg, np.ndarray):
            self.ahash.update(arg.view(np.uint8))
        elif isinstance(arg, list):
            [self._update_hash(a) for a in arg]
        else:
            self.ahash.update(str(arg).encode('utf-8'))