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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 _getFullPolicyName(policy_item,
                       policy_name,
                       return_full_policy_names,
                       adml_language):
    '''
    helper function to retrieve the full policy name if needed
    '''
    adml_data = _get_policy_resources(language=adml_language)
    if policy_name in adm_policy_name_map[return_full_policy_names]:
        return adm_policy_name_map[return_full_policy_names][policy_name]
    if return_full_policy_names and 'displayName' in policy_item.attrib:
        fullPolicyName = _getAdmlDisplayName(adml_data, policy_item.attrib['displayName'])
        if fullPolicyName:
            adm_policy_name_map[return_full_policy_names][policy_name] = fullPolicyName
            policy_name = fullPolicyName
    elif return_full_policy_names and 'id' in policy_item.attrib:
        fullPolicyName = _getAdmlPresentationRefId(adml_data, policy_item.attrib['id'])
        if fullPolicyName:
            adm_policy_name_map[return_full_policy_names][policy_name] = fullPolicyName
            policy_name = fullPolicyName
    policy_name = policy_name.rstrip(':').rstrip()
    return policy_name