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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 menu():
 """ Return global menu composed from all modules menu. This method will compose the global menu by calling menu() function for module, it should be located under module_path.menu module """

    root = MenuItem('')

    for mod in droplet.modules():
        if mod.installed:
            module_path = mod.__class__.__module__.rsplit('.', 1)[0]
            menu = import_module(module_path + '.menu')
            if menu:
                menu.menu(root)

    return root