def contourf(
    x: np.ndarray, y: np.ndarray, z: np.ndarray, ax: Axes, **kwargs: Any
) -> QuadContourSet:
    """
    Filled contour plot of 2D DataArray.

    Wraps :py:func:`matplotlib:matplotlib.pyplot.contourf`.
    """
    primitive = ax.contourf(x, y, z, **kwargs)
    return primitive

    Filled contour plot of 2D DataArray.

    Wraps :py:func:`matplotlib:matplotlib.pyplot.contourf`.
    
xarray/plot/dataarray_plot.py