def __init__(self, children=None, connector=None, negated=False):
        self.children = children and children[:] or []
        self.connector = connector or self.default
        self.subtree_parents = []
        self.negated = negated

    # We need this because of django.db.models.query_utils.Q. Q. __init__() is
    # problematic, but it is a natural Node subclass in all other respects.
Run the combiner for the given step.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/utils/tree.py/Node.__init__--crossover with--dataset/ETHPy150Open Yelp/mrjob/mrjob/job.py/MRJob.run_combiner