r, theta = symbols("r, theta")
graphics(
    contour(
        sin(2 * r) * cos(theta), (theta, 0, 2*pi), (r, 0, 7),
        rendering_kw={"levels": 100}
    ),
    polar_axis=True, aspect="equal"
)
# Expected:
## Plot object containing:
## [0]: contour: sin(2*r)*cos(theta) for theta over (0.0, 6.283185307179586) and r over (0.0, 7.0)