I am new to PostgreSQL/PostGIS and want to replicate a function from a Python script into a SQL query. In my Python script, I have a list of feature classes and I use ArcPy's `Merge_Management` to merge them together into a new layer called `s_stud`:

    study_lyr_list = ["region_1", "region_2", "region_3"]
    arcpy.Merge_management(studies_lyr_list, s_studs)

 I essentially have the same thing setup in PostGIS. I have tables for regions 1, 2, and 3 and I want to merge them together. They all share the same fields, so basically, I am just combining them together into a new `master` table. 

How would I do that as a query?

I have the PostGIS extensions.