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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 find_elb_dns_zone_id(name='', env='dev', region='us-east-1'):
 """Get an application's AWS elb dns zone id. Args: name (str):
 ELB name env (str):
 Environment/account of ELB region (str):
 AWS Region Returns: str: elb DNS zone ID """

    LOG.info('Find %s ELB DNS Zone ID in %s [%s].', name, env, region)
    client = boto3.Session(profile_name=env).client('elb', region_name=region)
    elbs = client.describe_load_balancers(LoadBalancerNames=[name])
    return elbs['LoadBalancerDescriptions'][0]['CanonicalHostedZoneNameID']