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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 im_detect(self, im_list, root_dir=None, extension=None, show_timer=False):
 """ wrapper for detecting multiple images Parameters: im_list : list of str image path or list of image paths root_dir : str directory of input images, optional if image path already has full directory information extension : str image extension, eg. ".jpg", optional Returns: """

        test_db = TestDB(im_list, root_dir=root_dir, extension=extension)
        test_iter = DetIter(test_db, 1, self.data_shape, self.mean_pixels,
                            is_train=False)
        return self.detect_iter(test_iter, show_timer)