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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _generate(cls, strategy, params):
 """generate the object. Args: params (dict):
 attributes to use for generating the object strategy: the strategy to use """

        if cls._meta.abstract:
            raise errors.FactoryError(
                "Cannot generate instances of abstract factory %(f)s; "
                "Ensure %(f)s.Meta.model is set and %(f)s.Meta.abstract "
                "is either not set or False." % dict(f=cls.__name__))

        step = builder.StepBuilder(cls._meta, params, strategy)
        return step.build()