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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 run_all(plot=True, seed=None):
 """ Run all examples. """

    if seed is not None:
        import random
        random.seed(seed)

    print("Running biggest_multiple.py")
    biggest_multiple.run(plot=plot)

    print("Running polynomials.py")
    polynomials.run(plot=plot)

    print("Running travelling_salesman.py")
    travelling_salesman.run(plot=plot)

    print("Running irrigation.py")
    irrigation.run()