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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 _render_border_line(self, t, settings):
 """ Render box border line. """

        s = self._es(settings, self.SETTING_WIDTH, self.SETTING_MARGIN, self.SETTING_MARGIN_LEFT, self.SETTING_MARGIN_RIGHT)
        w = self.calculate_width_widget(**s)
        s = self._es(settings, self.SETTING_BORDER_STYLE, self.SETTING_BORDER_FORMATING)
        border_line = self.fmt_border(w, t, **s)
        s = self._es(settings, self.SETTING_MARGIN, self.SETTING_MARGIN_LEFT, self.SETTING_MARGIN_RIGHT, self.SETTING_MARGIN_CHAR)
        border_line = self.fmt_margin(border_line, **s)
        return border_line