def __init__(self, document_part):
        """Initialize this chain.

        `document` is the :class:`Document` this chain is part of."""
        super().__init__(document_part)
        self.document_part = document_part
        self._init_state()
        self.containers = []
        self.done = True
def __init__ ( self , document_part ) : super ( ) . __init__ ( document_part ) self . document_part = document_part self . _init_state ( ) self . containers = [ ] self . done = True
Initialize this chain.

        `document` is the :class:`Document` this chain is part of.