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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 copy_selection_access_string(self):
 """Copys access_string to selection to the clipboard An access string is Python code to reference the selection If there is no selection then a reference to the current cell is copied """


        selection = self.get_selection()
        if not selection:
            cursor = self.grid.actions.cursor
            selection = Selection([], [], [], [], [tuple(cursor[:2])])
        shape = self.grid.code_array.shape
        tab = self.grid.current_table

        access_string = selection.get_access_string(shape, tab)

        # Copy access string to clipboard
        self.grid.main_window.clipboard.set_clipboard(access_string)

        # Display copy operation and access string in status bar
        statustext = _("Cell reference copied to clipboard: {access_string}")
        statustext = statustext.format(access_string=access_string)

        post_command_event(self.main_window, self.StatusBarMsg,
                           text=statustext)