code: def get_keys_from_shelve(file_name, file_location):
      
      temp_list = list()
      file = __os.path.join(file_location, file_name)
      shelve_store = __shelve.open(file)
      for key in shelve_store:
          temp_list.append(key)
      shelve_store.close()
      return temp_list
docs: Function to retreive all keys in a shelve
      Args:
          file_name: Shelve storage file name
          file_location: The location of the file, derive from the os module
  
      Returns:
          a list of the keys