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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 enable_caching(self, file_path=None):
 """Enables caching request-wide for all cacheable calls. * file_path: A file path for the backend storage file. If None set, a temp file would probably be created, according the backend. """


        if not file_path:
            file_path = tempfile.mktemp(prefix="pylast_tmp_")

        self.cache_backend = _ShelfCacheBackend(file_path)