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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 wait_for_healthy( raiden: 'RaidenService', node_address: Address, retry_timeout: float, ) -> None: """Wait until `node_address` becomes healthy. Note: This does not time out, use gevent.Timeout. """

    network_statuses = views.get_networkstatuses(
        views.state_from_raiden(raiden),
    )

    while network_statuses.get(node_address) != NODE_NETWORK_REACHABLE:
        gevent.sleep(retry_timeout)
        network_statuses = views.get_networkstatuses(
            views.state_from_raiden(raiden),
        )