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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def heading(self, column, option=None, **kw):
 """ 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 """

        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)