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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 swarm_service_info(service_name=str):
    '''
    Swarm Service Information

    service_name
        The name of the service that you want information on about the service

    CLI Example:

    .. code-block:: bash

        salt '*' swarm.swarm_service_info service_name=Test_Service
    '''
    try:
        salt_return = {}
        client = docker.APIClient(base_url='unix://var/run/docker.sock')
        service = client.inspect_service(service=service_name)
        getdata = salt.utils.json.dumps(service)
        dump = salt.utils.json.loads(getdata)
        version = dump['Version']['Index']
        name = dump['Spec']['Name']
        network_mode = dump['Spec']['EndpointSpec']['Mode']
        ports = dump['Spec']['EndpointSpec']['Ports']
        swarm_id = dump['ID']
        create_date = dump['CreatedAt']
        update_date = dump['UpdatedAt']
        labels = dump['Spec']['Labels']
        replicas = dump['Spec']['Mode']['Replicated']['Replicas']
        network = dump['Endpoint']['VirtualIPs']
        image = dump['Spec']['TaskTemplate']['ContainerSpec']['Image']
        for items in ports:
            published_port = items['PublishedPort']
            target_port = items['TargetPort']
            published_mode = items['PublishMode']
            protocol = items['Protocol']
            salt_return.update({'Service Name': name,
                                'Replicas': replicas,
                                'Service ID': swarm_id,
                                'Network': network,
                                'Network Mode': network_mode,
                                'Creation Date': create_date,
                                'Update Date': update_date,
                                'Published Port': published_port,
                                'Target Port': target_port,
                                'Published Mode': published_mode,
                                'Protocol': protocol,
                                'Docker Image': image,
                                'Minion Id': __context__['server_name'],
                                'Version': version})
    except TypeError:
        salt_return = {}
        salt_return.update({'Error': 'service_name arg is missing?'})
    return salt_return