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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 _proxy_info(minion_id, api_url, email, secret_key, fqdn_separator):
    '''
    retrieve a dict of a device that exists in nsot

    :param minion_id: str
    :param api_url: str
    :param email: str
    :param secret_key: str
    :param fqdn_separator: str
    :return: dict
    '''
    device_info = {}
    if fqdn_separator:
        minion_id = minion_id.replace('.', fqdn_separator)
    token = _get_token(api_url, email, secret_key)
    if token:
        headers = {'Authorization': 'AuthToken {}:{}'.format(email, token)}
        device_info = _query_nsot(api_url, headers, device=minion_id)

    return device_info