I would like my program to have a main function so I can run it as a module or main program. Main functions are new to me and I have no idea how to do this.
#!/usr/bin/python3
def main():
#left dashboard
    ld = raw_input("Left dashboard switch (0 or 1): ")
#right dashboard
    rd = raw_input("Right dasboard switch (0 or 1): ")
#child lock
    cl = raw_input("Child lock switch (0 or 1): ")
#master lock
    ml = raw_input("Master unlock switch (0 or 1): ")
#left inside
    li = raw_input("Left inside handle (0 or 1): ")
#left outside
    lo = raw_input("Left outside handle (0 or 1): ")
#right inside
    ri = raw_input("Right inside handle (0 or 1): ")
#right outside
    ro = raw_input("Right outside handle (0 or 1): ")
#gear shift
    gs = raw_input("Gear shift position (P, N, D , 1 ,2 ,3 or R): ")
    d = 0
    r = 0
    l = 0
    if gs == "P" and ml == "1" and cl == "0":
            d = 1
    if ri == "1" or ro == "1" or rd == "1":
            r = 1
    if li == "1" or lo == "1" or ld == "1":
            l = 1
    if d == 0:
            print "Both doors closed"
if _name_ == "_main_":
    main()
 
     
    