@classmethod<EOL><INDENT>def _new_instance(cls, children=None, connector=None, negated=False):<DEDENT>
obj = QBase(children, connector, negated)<EOL>obj.__class__ = cls<EOL>return obj<EOL>
Create a new instance of this class when new Nodes (or subclasses) are
needed in the internal code in this class. Normally, it just shadows
__init__(). However, subclasses with an __init__ signature that aren't
an extension of Node.__init__ might need to implement this method to
allow a Node to create a new instance of them (if they have any extra
setting up to do).