def find_pst_folder(mapi, pst_filepath):
    dispatch = win32com.client.gencache.EnsureDispatch
    for store in dispatch(mapi.Stores):
        if store.IsDataFileStore and store.FilePath == pst_filepath:
            return store.GetRootFolder()


def get_pst_folder(pst_filepath):
    """Returns the PST archive folder, if it doesn't exist it creates it"""
    outlook = win32com.client.Dispatch("Outlook.Application").GetNamespace("MAPI")
    const = win32com.client.constants
    # get pst folder
    pst_folder = find_pst_folder(outlook, pst_filepath)

    # if not found
    if not pst_folder:
        outlook.AddStoreEx(pst_filepath, const.olStoreDefault)
        pst_folder = find_pst_folder(outlook, pst_filepath)
        # add archive folder
        pst_folder.Folders.Add('Archive')
        # set the account name
        path_list = str.split(pst_filepath, '\\')
        displayname = path_list[len(path_list)-1].replace('.pst', '')
        pst_folder.Name = displayname
    if not pst_folder:
        raise RuntimeError("Can't find PST folder at %s" % pst_filepath)

    # return archive folder
#    archive_folder = pst_folder.GetDefaultFolder.Folders('Archive')
    return pst_folder