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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 _apply(self, element, key=None):
 """ Applies the operation to the element, executing any pre- and post-processor hooks if defined. """

        kwargs = {}
        for hook in self._preprocess_hooks:
            kwargs.update(hook(self, element))
        ret = self._process(element, key)
        for hook in self._postprocess_hooks:
            ret = hook(self, ret, **kwargs)
        return ret