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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 print_help(model, defaults=None):
 """Print help for the command line arguments of the given model. Parameters model : sklearn.base.BaseEstimator The basic model, e.g. a ``NeuralNet`` or sklearn ``Pipeline``. defautls : dict or None (default=None) Optionally, change the default values to use custom defaults. Commandline arguments have precedence over defaults. """

    defaults = defaults or {}

    print("This is the help for the model-specific parameters.")
    print("To invoke help for the remaining options, run:")
    print("python {} -- --help".format(sys.argv[0]))
    print()

    lines = (_get_help_for_estimator(prefix, estimator, defaults=defaults) for
             prefix, estimator in _yield_estimators(model))
    print('\n'.join(chain(*lines)))