code: def insert_colorpoint(self, position=0.5, color1=[1.0,1.0,0.0], color2=[1.0,1.0,0.0]):
          
          L = self._colorpoint_list
  
          # if position = 0 or 1, push the end points inward
          if   position <= 0.0:
              L.insert(0,[0.0,color1,color2])
  
          elif position >= 1.0:
              L.append([1.0,color1,color2])
  
          # otherwise, find the position where it belongs
          else:
  
              # loop over all the points
              for n in range(len(self._colorpoint_list)):
                  # check if it's less than the next one
                  if position <= L[n+1][0]:
                      # found the place to insert it
                      L.insert(n+1,[position,color1,color2])
                      break
  
          # update the image with the new cmap
          self.update_image()
  
          return self
docs: Inserts the specified color into the list.