code: def from_dict(cls, d):
          
          assert isinstance(d, dict)
          init_args = dict()
          for key, is_required in cls.dictionary_attributes.iteritems():
              try:
                  init_args[key] = d[key]
              except KeyError:
                  if is_required:
                      raise DictConvertible.Error('missing key in dictionary', cls, missing_key=key)
          return cls(**init_args)
docs: Create an instance from a dictionary.