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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 add_item(c, name, item):
 """ add_item adds MenuItems to the menu identified by 'name' """

        if isinstance(item, MenuItem):
            if name not in c.items:
                c.items[name] = []
            c.items[name].append(item)
            c.sorted[name] = False