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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 difficulties_by_voivodeship(voivodeship, dt=datetime.now()):
 """ Get difficulties in voivodeship. :param voivodeship: Voivodeship numeric value. :param dt: Datetime for data. Default: datetime.now() :return: List of difficulties by voivodeship. """

    session = requests.Session()
    session.headers.update({'User-Agent': USER_AGENT})
    session.headers.update({'X-Requested-With': 'XMLHttpRequest'})
    
    session.get('{}/Mapa/'.format(HOST))
    
    url = '{}/Mapa/PodajUtrudnieniaWWojewodztwie?KodWojewodztwa={}&_={}'.format(HOST, str(voivodeship), _datetime_to_asp_date(dt))
    response = session.get(url)
    
    json_data = response.json() if len(response.text) > 0 else []
    return json_data