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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 create_request(query):
 """ Creates a GET request to Yarr! server :param query: Free-text search query :returns: Requests object """

    yarr_url = app.config.get('YARR_URL', False)

    if not yarr_url:
        raise('No URL to Yarr! server specified in config.')

    api_token = app.config.get('YARR_API_TOKEN', False)
    headers = {'X-API-KEY': api_token} if api_token else {}
    payload = {'q': query}
    url = '%s/search' % yarr_url

    return requests.get(url, params=payload, headers=headers)