compute_boundary_facets returns booleans?

[RemDelaporteMathurin]

In the first demo, the function dolfinx.mesh.compute_boundary_facets is said to return an array of booleans where it seems to return 0 or 1. Should it be fixed? or is it something I got wrong?

... using dolfinx.mesh.compute_boundary_facets. This function returns an array of booleans of the same size as the number of facets on this processor, where True indicates that the local facet is on the boundary

Thanks for the tutorial!