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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_cache(self):
 """Reset the lal cache. This can be used to update the cache if the result may change due to more files being added to the filesystem, for example. """

        cache = locations_to_cache(self.frame_src, latest=True)
        stream = lalframe.FrStreamCacheOpen(cache)
        self.stream = stream