@staticmethod
def gui_dict():
    """
        Return a dictionary with functions that will be shown in the
        configuration gui for the calculator node.

        Each dictionary in the globals_dict represents another level of
        subcategories in the tree view. The keys of the dict is used as labels
        for the subcategories. A list represents a list of functions.

        Each function in the list should be a tuple of three elements: label,
        code, tooltip/documentation.

        For example:

        {'My functions': [
            ('My function 1', 'myplugin.func1()',
             "My function 1 is awesome..."),
            ('My function 2', 'myplugin.func2()',
             "My function 1 is also awesome...")]}

        This should result in a top level category called "My functions"
        containing the two functions "My function 1" and "My function 2".
        """
    return {}
