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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_config(cls, config, name, section_key="segmenters"):
 """ Constructs a segmenter from a configuration doc. """

        section = config[section_key][name]
        segmenter_class_path = section['class']
        Segmenter = yamlconf.import_module(segmenter_class_path)
        return Segmenter.from_config(config, name, section_key=section_key)