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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 _serve_dir(self, abspath, params):
 """Show a directory listing."""

    relpath = os.path.relpath(abspath, self._root)
    breadcrumbs = self._create_breadcrumbs(relpath)
    entries = [{'link_path': os.path.join(relpath, e), 'name': e} for e in os.listdir(abspath)]
    args = self._default_template_args('dir.html')
    args.update({'root_parent': os.path.dirname(self._root),
                 'breadcrumbs': breadcrumbs,
                 'entries': entries,
                 'params': params})
    content = self._renderer.render_name('base.html', args).encode("utf-8")
    self._send_content(content, 'text/html')