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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 translate(text, target_lang='en', source_lang=None):
 	""" 	Use the Google v2 API to translate the text. You had better have set 	the API key on this function before calling it. 	"""

	url_base = 'https://www.googleapis.com/language/translate/v2'
	params = dict(
		key=translate.API_key,
		q=text,
		target=target_lang,
	)
	if source_lang:
		params['source'] = source_lang
	resp = requests.get(url_base, params=params)
	resp.raise_for_status()
	return resp.json()['data']['translations'][0]['translatedText']