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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 pre_run_hook(self, func, prefix=None):
 """ Decorator to add a pre-run hook to this ingredient. Pre-run hooks are captured functions that are run, just before the main function is executed. """

        cf = self.capture(func, prefix=prefix)
        self.pre_run_hooks.append(cf)
        return cf