code: def get_tip_label_coords(self):
          
          # number of tips
          ns = self.ttree.ntips
  
          # x-coordinate of tips assuming down-face
          tip_xpos = self.coords.verts[:ns, 0]
          tip_ypos = self.coords.verts[:ns, 1]
          align_edges = None
          align_verts = None
  
          # handle orientations
          if self.style.orient in (0, 'down'):
              # align tips at zero
              if self.style.tip_labels_align:
                  tip_yend = np.zeros(ns)
                  align_edges = np.array([
                      (i + len(tip_ypos), i) for i in range(len(tip_ypos))
                  ])
                  align_verts = np.array(
                      list(zip(tip_xpos, tip_ypos)) + \
                      list(zip(tip_xpos, tip_yend))
                  )
                  tip_ypos = tip_yend
          else:
              # tip labels align finds the zero axis for orientation...
              if self.style.tip_labels_align:
                  tip_xend = np.zeros(ns)
                  align_edges = np.array([
                      (i + len(tip_xpos), i) for i in range(len(tip_xpos))
                  ])
                  align_verts = np.array(
                      list(zip(tip_xpos, tip_ypos)) + \
                      list(zip(tip_xend, tip_ypos))
                  )
                  tip_xpos = tip_xend
          return tip_xpos, tip_ypos, align_edges, align_verts
docs: Get starting position of tip labels text based on locations of the 
          leaf nodes on the tree and style offset and align options. Node
          positions are found using the .verts attribute of coords and is 
          already oriented for the tree face direction.