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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 get_route53_client(agent, region, cooperator=None):
 """ Get a non-registration Route53 client. """

    if cooperator is None:
        cooperator = task
    return region.get_client(
        _Route53Client,
        agent=agent,
        creds=region.creds,
        region=REGION_US_EAST_1,
        endpoint=AWSServiceEndpoint(_OTHER_ENDPOINT),
        cooperator=cooperator,
    )