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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 from_argparse(cls, opts):
 """ Initialize an instance of the metricParameters class from an argparse.OptionParser instance. This assumes that insert_metric_calculation_options and verify_metric_calculation_options have already been called before initializing the class. """

        return cls(opts.pn_order, opts.f_low, opts.f_upper, opts.delta_f,\
                   f0=opts.f0, write_metric=opts.write_metric)