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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 _parse_bbox_grid(bbox_grid):
 """ Helper method for parsing bounding box grid. It will try to parse it into `BBoxCollection` """

        if isinstance(bbox_grid, BBoxCollection):
            return bbox_grid

        if isinstance(bbox_grid, list):
            return BBoxCollection(bbox_grid)

        raise ValueError("Parameter 'bbox_grid' should be an instance of {}".format(BBoxCollection.__name__))