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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 line_on_device( device: 'cirq.google.XmonDevice', length: int, method: LinePlacementStrategy = greedy.GreedySequenceSearchStrategy() ) -> GridQubitLineTuple: """Searches for linear sequence of qubits on device. Args: device: Google Xmon device instance. length: Desired number of qubits making up the line. method: Line placement method. Defaults to cirq.greedy.GreedySequenceSearchMethod. Returns: Line sequences search results. """

    return method.place_line(device, length)