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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 generate_error_message(tag, err_uniq, err_appl, err_mult):
 """ Generate the error message for an object. """

    err = []
    if err_uniq:
        err.append('Uniqueness restriction: item type %s' % tag.item_type)
    if err_appl:
        err.append('Applicability restriction: field %s' % tag.field)
    if err_mult:
        err.append('Multiplicity restriction: field %s' % tag.field)
    return err