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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 cumulative_window(group_by=None, order_by=None):
 """Create a cumulative window for use with aggregate window functions. All window frames / ranges are inclusive. Parameters group_by : expressions, default None Either specify here or with TableExpr.group_by order_by : expressions, default None For analytic functions requiring an ordering, specify here, or let Ibis determine the default ordering (for functions like rank) Returns ------- Window """

    return Window(
        preceding=None, following=0, group_by=group_by, order_by=order_by
    )