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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 start_pipeline(conf, args):
 """Start a pipeline"""

    host = conf.config['instances'][args.host_instance]
    url = api.build_pipeline_url(build_instance_url(host))
    auth = tuple([conf.creds['instances'][args.host_instance]['user'], conf.creds['instances'][args.host_instance]['pass']])
    runtime_parameters = {}
    verify_ssl = host.get('verify_ssl', True)
    if args.runtime_parameters:
        runtime_parameters = json.loads(args.runtime_parameters)
    start_result = api.start_pipeline(url, args.pipeline_id, auth, verify_ssl, runtime_parameters)

    return start_result