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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(from_currency, to_currency):
 	""" update from_currency to_currency pair in cache if 	last update for that pair is over 30 minutes ago by request API info """

	if check_update(from_currency, to_currency) is True:
		ccache[from_currency][to_currency]['value'] = convert_using_api(from_currency, to_currency)
		ccache[from_currency][to_currency]['last_update'] = time.time()
		cache.write(ccache)