text: # Copyright 2014, Rackspace US, Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  #
  # (c) 2014, Kevin Carter <kevin.carter@rackspace.com>
  # (c) 2015, Major Hayden <major@mhtx.net>
  #
  
  
  def merge_dict(base_items, new_items):
      """Recursively merge new_items into some base_items.
  
      If an empty dictionary is provided as a new value, it will
      completely replace the existing dictionary.
  
      :param base_items: ``dict``
      :param new_items: ``dict``
      :return dictionary:
      """
      for key, value in new_items.items():
          if isinstance(value, dict) and value:
              base_merge = merge_dict(base_items.get(key, {}), value)
              base_items[key] = base_merge
          else:
              base_items[key] = new_items[key]
      return base_items
  
  
  def append_if(array, item):
      """Append an ``item`` to an ``array`` if its not already in it.
  
      :param array: ``list``  List object to append to
      :param item: ``object``  Object to append to the list
      :returns bool:  Flag indicating whether the append happened (True)
          or not (False)
      """
      if item not in array:
          array.append(item)
          return True
      return False
  
  
  def recursive_list_removal(base_list, purge_list):
      """Remove items from a list.
  
      If base_list and purge_list resolve to the same list in memory,
      only the first item will be removed due to Python's handling of mutation
      during iteration.
  
      :param base_list: ``list`` List representing base_list entries
      :param purge_list: ``list`` List of items to remove
      """
      for item in purge_list:
          for _item in base_list:
              if item == _item:
                  base_list.pop(base_list.index(item))
  
  
  # TODO(nrb): this probably needs to be renamed, as it's not really recursive
  def recursive_dict_removal(inventory, purge_list):
      """Remove items from a dictionary.
  
      Only items in child dictionaries and lists are removed.
  
      Dictionary keys can only be deleted at the 3rd level (e.g in
      inventory['top']['middle']['bottom'], only 'bottom' would be targeted by
      this function)
  
      :param inventory: ``dict`` Dictionary representing the inventory
      :param purge_list: ``list`` List of items to remove
      """
      for key, value in inventory.items():
          if isinstance(value, dict):
              for child_key, child_value in value.items():
                  if isinstance(child_value, dict):
                      for item in purge_list:
                          if item in child_value:
                              del(child_value[item])
                  elif isinstance(child_value, list):
                      recursive_list_removal(child_value, purge_list)
          elif isinstance(value, list):
              recursive_list_removal(value, purge_list)
  