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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 get_overlay_label(cls, overlay, default_label=''):
 """ Returns a label if all the elements of an overlay agree on a consistent label, otherwise returns the default label. """

        if all(el.label==overlay.get(0).label for el in overlay):
            return overlay.get(0).label
        else:
            return default_label