How to use the deid.identifiers.actions.perform_action function in deid

# Keep track of the fields we've seen, not to blank them
    seen = []
    for action in deid['header']:
        item,fields = perform_action(item=item,
                                     action=action,
                                     return_seen=True)
        seen = seen + [f for f in fields if f not in seen]
    remaining = [x for x in item.keys() if x not in seen]

    # Apply default action to remaining fields
    if len(remaining) > 0 and default != "KEEP":
        bot.debug("%s fields set for default action %s" %(len(remaining),default))
        for field in remaining:
            action = {'action': default, "field":field}
            item = perform_action(item=item, action=action)
    return item

def _clean_item(item, deid, default="KEEP"):
    '''clean a single item according to a deid specification.
    This function is expected to be called from clean_identifiers
    below

    Parameters
    ==========
    item: the item dictionary to clean
    deid: the already loaded deid, with a header section with 
          actions to specify how to clean
    '''

    # Keep track of the fields we've seen, not to blank them
    seen = []
    for action in deid['header']:
        item,fields = perform_action(item=item,
                                     action=action,
                                     return_seen=True)
        seen = seen + [f for f in fields if f not in seen]
    remaining = [x for x in item.keys() if x not in seen]

    # Apply default action to remaining fields
    if len(remaining) > 0 and default != "KEEP":
        bot.debug("%s fields set for default action %s" %(len(remaining),default))
        for field in remaining:
            action = {'action': default, "field":field}
            item = perform_action(item=item, action=action)
    return item