'Set the capstyle as a string in (\'butt\', \'round\', \'projecting\')'

def set_capstyle(self, cs):

    DEBUG_MSG(u'set_capstyle()', 1, self)
    self.select()
    GraphicsContextBase.set_capstyle(self, cs)
    self._pen.SetCap(GraphicsContextWx._capd[self._capstyle])
    self.gfx_ctx.SetPen(self._pen)
    self.unselect()
