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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 set_scanner_strength(zap_helper, scanners, strength):
 """Set the attack strength for scanners."""

    if not scanners or 'all' in scanners:
        scanners = _get_all_scanner_ids(zap_helper)

    with zap_error_handler():
        zap_helper.set_scanner_attack_strength(scanners, strength)

    console.info('Set attack strength to {0}.'.format(strength))