code: def _bar(self, serie, parent, x, y, i, zero, secondary=False):
          
          width = (self.view.x(1) - self.view.x(0)) / self._len
          x, y = self.view((x, y))
          series_margin = width * self._series_margin
          x += series_margin
          width -= 2 * series_margin
          width /= self._order
          if self.horizontal:
              serie_index = self._order - serie.index - 1
          else:
              serie_index = serie.index
          x += serie_index * width
  
          serie_margin = width * self._serie_margin
          x += serie_margin
          width -= 2 * serie_margin
          height = self.view.y(zero) - y
          r = serie.rounded_bars * 1 if serie.rounded_bars else 0
          alter(
              self.svg.transposable_node(
                  parent,
                  'rect',
                  x=x,
                  y=y,
                  rx=r,
                  ry=r,
                  width=width,
                  height=height,
                  class_='rect reactive tooltip-trigger'
              ), serie.metadata.get(i)
          )
          return x, y, width, height
docs: Internal bar drawing function