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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 weld_tail(array, length, n):
 """Return the last n elements. Parameters array : numpy.ndarray or WeldObject Array to select from. length : int or WeldObject Length of the array. Int if already known can simplify the computation. n : int How many values. Returns ------- WeldObject Representation of the computation. """

    obj_id, weld_obj = create_weld_object(array)
    if isinstance(length, WeldObject):
        length = get_weld_obj_id(weld_obj, length)
        slice_start = '{} - {}L'.format(length, n)
        slice_stop = '{}'.format(length)
    else:
        slice_start = '{}L - {}L'.format(length, n)
        slice_stop = '{}L'.format(length)

    weld_template = """slice(
    {array},
    {slice_start},
    {slice_stop}
)"""

    weld_obj.weld_code = weld_template.format(array=obj_id,
                                              slice_start=slice_start,
                                              slice_stop=slice_stop)

    return weld_obj