def __init__(self,
                 primary=None,
                 secondary=None,
                 ignore_case=True,
                 ignore_deleted=False):

        if not primary:
            primary = ("name",)
        self.primary = set(primary)

        if not secondary:
            self.secondary = set()
        else:
            self.secondary = set(secondary)

        self.ignore_case = ignore_case
        self.ignore_deleted = ignore_deleted

    # -------------------------------------------------------------------------
These should both work without a problem.
dataset/ETHPy150Open sahana/eden/modules/s3/s3import.py/S3Duplicate.__init__--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.2/tests/regressiontests/inline_formsets/tests.py/InlineFormsetFactoryTest.test_inline_formset_factory