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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 fmt_border(self, width, t = 'm', border_style = 'utf8.a', border_formating = {}):
 """ Format box separator line. """

        border = self.bchar('l', t, border_style) + (self.bchar('h', t, border_style) * (width-2)) + self.bchar('r', t, border_style)
        return self.fmt_text(border, **border_formating)