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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 send(transport, time, state, host, description, service, tag, attribute, ttl, metric_f, echo):
 """Send a single event to Riemann"""

    client = CommandLineClient(transport)
    event = client.create_event({
        'time': time,
        'state': state,
        'host': host,
        'description': description,
        'service': service,
        'tags': tag,
        'attributes': dict(attribute),
        'ttl': ttl,
        'metric_f': metric_f
    })

    with client:
        client.send_event(event)
    if echo:
        echo_event(client.create_dict(event))