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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 validate_item_cmd(description, price, quantity, reference=None):
 """ Create a commando to save items from the order. A list of items or commands must be created to save a order @param description: Item's description @param price: Item's price @param quantity: Item's quantity @param reference: a product reference for the item. Must be a Node @return: A Command that validate and save a item """

    return ValidateItemCmd(description=description, price=price, quantity=quantity, reference=reference)