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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_hosted_zone_by_name(client, zone_name):
 """Get the zone id of an existing zone by name. Args: client (:class:`botocore.client.Route53`):
 The connection used to interact with Route53's API. zone_name (string):
 The name of the DNS hosted zone to create. Returns: string: The Id of the Hosted Zone. """

    p = client.get_paginator("list_hosted_zones")

    for i in p.paginate():
        for zone in i["HostedZones"]:
            if zone["Name"] == zone_name:
                return parse_zone_id(zone["Id"])
    return None