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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 status_schedule(token):
 """ Returns the json string from the Hydrawise server after calling statusschedule.php. :param token: The users API token. :type token: string :returns: The response from the controller. If there was an error returns None. :rtype: string or None """


    url = 'https://app.hydrawise.com/api/v1/statusschedule.php'

    payload = {
        'api_key': token,
        'hours': 168}

    get_response = requests.get(url, params=payload, timeout=REQUESTS_TIMEOUT)

    if get_response.status_code == 200 and \
       'error_msg' not in get_response.json():
        return get_response.json()

    return None