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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 get_bb_intersections(recording):
 """ Get all intersections of the bounding boxes of strokes. Parameters recording : list of lists of integers Returns ------- A symmetrical matrix which indicates if two bounding boxes intersect. """

    intersections = numpy.zeros((len(recording), len(recording)),
                                dtype=bool)
    for i in range(len(recording)-1):
        a = geometry.get_bounding_box(recording[i]).grow(0.2)
        for j in range(i+1, len(recording)):
            b = geometry.get_bounding_box(recording[j]).grow(0.2)
            intersections[i][j] = geometry.do_bb_intersect(a, b)
            intersections[j][i] = intersections[i][j]
    return intersections