code: def heading(self, column, option=None, **kw):
          
          if kw:
              # Set the default image of the heading to the drag icon
              kw.setdefault("image", self._im_drag)
              self._visual_drag.heading(ttk.Treeview.column(self, column, 'id'), option, **kw)
          return ttk.Treeview.heading(self, column, option, **kw)
docs: Query or modify the heading options for the specified column.
  
          If `kw` is not given, returns a dict of the heading option values. If
          `option` is specified then the value for that option is returned.
          Otherwise, sets the options to the corresponding values.
  
          :param text: text to display in the column heading
          :type text: str
          :param image: image to display to the right of the column heading
          :type image: PhotoImage
          :param anchor: "n", "ne", "e", "se", "s", "sw", "w", "nw", or "center":
                         alignement of the heading text
          :type anchor: str
          :param command: callback to be invoked when the heading label is pressed.
          :type command: function