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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 get_b(self):
 """Returns the bottom border of the cell"""


        start_point, end_point = self._get_bottom_line_coordinates()
        width = self._get_bottom_line_width()
        color = self._get_bottom_line_color()

        return CellBorder(start_point, end_point, width, color)