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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 enable_policies(zap_helper, policy_ids):
 """ Set the enabled policies to use in a scan. When you enable a selection of policies, all other policies are disabled. """

    if not policy_ids:
        policy_ids = _get_all_policy_ids(zap_helper)

    with zap_error_handler():
        zap_helper.enable_policies_by_ids(policy_ids)