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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 el_is_empty(el):
 """Return ``True`` if tuple ``el`` represents an empty XML element."""

    if len(el) == 1 and not isinstance(el[0], (list, tuple)):
        return True
    subels_are_empty = []
    for subel in el:
        if isinstance(subel, (list, tuple)):
            subels_are_empty.append(el_is_empty(subel))
        else:
            subels_are_empty.append(not bool(subel))
    return all(subels_are_empty)