code: def get_edge_color(self, increment=1):
          
  
          i = self.edge_colors_index
  
          self.edge_colors_index += increment
          if self.edge_colors_index >= len(self.edge_colors):
              self.edge_colors_index = self.edge_colors_index-len(self.edge_colors)
              if self.edge_colors_index >= len(self.edge_colors): self.edge_colors_index=0 # to be safe
  
          return self.edge_colors[i]
docs: Returns the current face, then increments the face by what's specified