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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 get(self, prefix, url, schema_version=None):
 """ Get the cached object """

        if not self.cache_dir:
            return None

        filename = self._get_cache_file(prefix, url)

        try:
            with open(filename, 'rb') as file:
                item = pickle.load(file)
            if schema_version and schema_version != item.schema:
                LOGGER.debug("Cache get %s %s: Wanted schema %d, got %d",
                             prefix, url,
                             schema_version, item.schema)
                return None
            return item
        except FileNotFoundError:
            pass
        except Exception:  # pylint:disable=broad-except
            _, msg, _ = sys.exc_info()
            LOGGER.warning("Cache get %s %s failed: %s", prefix, url, msg)

        return None