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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 date_struct_nn(year, month, day, tz="UTC"):
 """ Assemble a date object but if day or month is none set them to 1 to make it easier to deal with partial dates """

    if not day:
        day = 1
    if not month:
        month = 1
    return date_struct(year, month, day, tz)