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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_list(bbox_list):
 """ Helper method for parsing a list of bounding boxes """

        if isinstance(bbox_list, BBoxCollection):
            return bbox_list.bbox_list, bbox_list.crs

        if not isinstance(bbox_list, list) or not bbox_list:
            raise ValueError('Expected non-empty list of BBox objects')

        for bbox in bbox_list:
            if not isinstance(bbox, BBox):
                raise ValueError('Elements in the list should be of type {}, got {}'.format(BBox.__name__, type(bbox)))

        crs = bbox_list[0].crs
        for bbox in bbox_list:
            if bbox.crs is not crs:
                raise ValueError('All bounding boxes should have the same CRS')

        return bbox_list, crs