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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 plot(f, lcar=1.0e-1):
 """Plot function over a disk. """

    import matplotlib
    import matplotlib.pyplot as plt
    import pygmsh

    geom = pygmsh.built_in.Geometry()
    geom.add_circle([0.0, 0.0, 0.0], 1.0, lcar, num_sections=4, compound=True)
    points, cells, _, _, _ = pygmsh.generate_mesh(geom, verbose=True)

    x = points[:, 0]
    y = points[:, 1]
    triang = matplotlib.tri.Triangulation(x, y, cells["triangle"])

    plt.tripcolor(triang, f(points.T), shading="flat")
    plt.colorbar()

    # Choose a diverging colormap such that the zeros are clearly
    # distinguishable.
    plt.set_cmap("coolwarm")
    # Make sure the color map limits are symmetric around 0.
    clim = plt.gci().get_clim()
    mx = max(abs(clim[0]), abs(clim[1]))
    plt.clim(-mx, mx)

    # circle outline
    circle = plt.Circle((0, 0), 1.0, edgecolor="k", fill=False)
    plt.gca().add_artist(circle)

    plt.gca().set_aspect("equal")
    plt.axis("off")
    return