import multiprocessing
import psycopg2

def my_subprocess():
    psycopg2.connect("host=localhost gssencmode=disable")
    print('child ok')

psycopg2.connect("host=localhost gssencmode=disable")
print('main ok')

p = multiprocessing.Process(target=my_subprocess)
p.start()
p.join()
print(p.exitcode)