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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 add_barplot(self):
 """ Generate the Samblaster bar plot. """

        cats = OrderedDict()
        cats['n_nondups'] = {'name': 'Non-duplicates'}
        cats['n_dups'] = {'name': 'Duplicates'}

        pconfig = {
            'id': 'samblaster_duplicates',
            'title': 'Samblaster: Number of duplicate reads',
            'ylab': 'Number of reads'
        }
        self.add_section( plot = bargraph.plot(self.samblaster_data, cats, pconfig) )