We have a total of 908 communities (each community has a number of households) which are located in the sphere of influence of roads / highways (social inclusion and logistics corridors), they are divided into groups (intervention and control) and They belong to 2 strata: near and far (with respect to the capital of the community). A community should be selected with a probability proportional to the number of households in each community within each strata, each type of road / highway and group to which it belongs. What command in Stata could be used to make the community selection with PPS?