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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 _populate_label_legacy_structures():
 """ We contain this code inside a function so that the imports we do in here are not visible at the module level. """

    global DIE_CUT_LABEL, ENDLESS_LABEL, ROUND_DIE_CUT_LABEL
    global label_sizes, label_type_specs

    from brother_ql.labels import FormFactor
    DIE_CUT_LABEL =       FormFactor.DIE_CUT
    ENDLESS_LABEL =       FormFactor.ENDLESS
    ROUND_DIE_CUT_LABEL = FormFactor.ROUND_DIE_CUT

    from brother_ql.labels import LabelsManager
    lm = LabelsManager()
    label_sizes = list(lm.iter_identifiers())
    for label in lm.iter_elements():
        l = {}
        l['name'] = label.name
        l['kind'] = label.form_factor
        l['color'] = label.color
        l['tape_size'] = label.tape_size
        l['dots_total'] = label.dots_total
        l['dots_printable'] = label.dots_printable
        l['right_margin_dots'] = label.offset_r
        l['feed_margin'] = label.feed_margin
        l['restrict_printers'] = label.restricted_to_models
        label_type_specs[label.identifier] = l