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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 cache_clear(self):
 		"""Purge the local store of all cached function information."""

		with self.cache_lock:
			cursor = self.cache_db.cursor()
			cursor.execute('DELETE FROM cache')
			self.cache_db.commit()
		self.logger.info('the RPC cache has been purged')
		return