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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 _build_package_finder(self, options, index_urls):
 """ Create a package finder appropriate to this install command. This method is meant to be overridden by subclasses, not called directly. """

        return PackageFinder(find_links=options.find_links,
                             index_urls=index_urls,
                             use_mirrors=options.use_mirrors,
                             mirrors=options.mirrors)