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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 concentric_hexagons(radius, start=(0, 0)):
 """A generator which produces coordinates of concentric rings of hexagons. Parameters radius : int Number of layers to produce (0 is just one hexagon) start : (x, y) The coordinate of the central hexagon. """

    x, y = start
    yield (x, y)
    for r in range(1, radius + 1):
        # Move to the next layer
        y -= 1
        # Walk around the hexagon of this radius
        for dx, dy in [(1, 1), (0, 1), (-1, 0), (-1, -1), (0, -1), (1, 0)]:
            for _ in range(r):
                yield (x, y)
                x += dx
                y += dy