docs: def initialize_fields(self, content):
          """ Initializes the :class:`Field` items in the `Sequence` with
          the *values* in the *content* list.
  
          :param list content: a list contains the :class:`Field` values for each
              item in the `Sequence`.
          """
          for name, pair in enumerate(zip(self, content)):
              item, value = pair
              # Container or Pointer
              if is_mixin(item):
                  item.initialize_fields(value)
              # Fields
              elif is_field(item):
                  item.value = value
              else:
                  raise MemberTypeError(self, item, name)