:param url: (str): the host url in the form 'http://host:port/'.
    :param pipeline_id: (string) the pipeline identifier
    :param auth: (tuple) a tuple of username, password
    :return: (boolean)

def pipeline_exists(url, pipeline_id, auth, verify_ssl):
    '''
    :param url: (str): the host url in the form 'http://host:port/'.
    :param pipeline_id: (string) the pipeline identifier
    :param auth: (tuple) a tuple of username, password
    :return: (boolean)
    '''
    try:
        pipeline_status(url, pipeline_id, auth, verify_ssl)['status']
        return True
    except requests.HTTPError:
        return False