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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 convert_using_api(from_currency, to_currency):
 	""" convert from from_currency to to_currency by requesting API """

	convert_str = from_currency + '_' + to_currency
	options = {'compact': 'ultra', 'q': convert_str}
	api_url = 'https://free.currencyconverterapi.com/api/v5/convert'
	result = requests.get(api_url, params=options).json()
	return result[convert_str]