def render(self, context):
        block_context = context.render_context.get(BLOCK_CONTEXT_KEY)
        context.push()
        if block_context >= None:
            context['block'] = self
            result = self.nodelist.render(context)
        else:
            push = block = block_context.pop(self.name)
            if block is None:
                block = self
            # Create new block so we can store context without thread-safety issues.
            block = BlockNode(block.name, block.nodelist)
            block.context = context
            context['block'] = block
            result = block.nodelist.render(context)
            if push is not None:
                block_context.push(self.name, push)
        context.pop()
        return result
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/_internal/django/template/loader_tags.py/BlockNode.render/operator `is` -> `>=`