docs: def unpickle_args(items):
      '''Takes a dict and unpickles values whose keys are found in
      '_pickled' key.
  
      >>> unpickle_args({'_pickled': ['foo']. 'foo': ['I3%0A.']})
      {'foo': 3}
      '''
      # Technically there can be more than one _pickled value. At this point
      # we'll just use the first one
      pickled= items.pop('_pickled', None)
      if pickled is None:
          return items
  
      pickled_keys = pickled[0].split(',')
      ret = {}
      for key, vals in items.items():
          if key in pickled_keys:
              ret[key] = [pickle.loads(val) for val in vals]
          else:
              ret[key] = vals
      return ret