Импорт функции из класса в другой файл?

Я пишу программу на Python для развлечения, но застрял при попытке импортировать функцию из класса в другой файл. Вот мой код:

#jurassic park mainframe

from random import randint
from sys import exit
from comm_system import Comm_system #the file i want to import from



class Jpark_mainframe(object):
    def mainframe_home(self):
        print "=====Welcome to the Jurassic Park Mainframe====="
        print "==========Security Administration==============="
        print "===========Communications Systems==============="
        print "===============System Settings=================="
        print "===================Quit========================="

        prompt = raw_input("What would you like to do? ")

        while prompt != "Quit":

            if prompt == "Security Administration":
                print "Please enter the 5-digit passcode:"
                security_passcode = "%d%d%d%d%d" % (2, 0, 1, 2, randint(1, 2))
                security_guess = raw_input(": ")
                security_guesses = 0

                while security_guess != security_passcode and security_guesses < 7:
                    print "Incorrect. Please enter the security passcode."
                    security_guesses += 1
                    security_guess = raw_input(": ")

                    if security_guess == security_passcode:
                        print "=========Security Administration======="
                        print "Area 1 Fences: Off"
                        print "Area 2 Fences: On"
                        print "Area 3 Fences: Off"
                        print "Velociraptor Compound: Off"
                        print "Lobby Security System: Off"
                        print "Entrance Facility System: Off"
                        print "To enable all systems, enter 'On'"


                        enable_security = raw_input(": ")

                        if enable_security == "On":
                            print "Systems Online."


            if prompt == "System Settings":
                print "You do not have access to system settings."
                exit(0)


            if prompt == "Communications Systems":
                print "===========Communications Systems==========="
                print "error: 'comm_link' missing in directories"
                exit(0)
            return Comm_system.run #this is where I want to return the 
                                                   #the other file

the_game = jpark_mainframe()
the_game.mainframe_home()

Я хочу вернуть функцию с именем run () из класса в другом файле. Когда я импортирую файл, он сначала запускает класс с run () в нем, а затем приступает к выполнению исходного кода. Почему так происходит?

Вот код из comm_system:

#communication systems


from sys import exit

class Comm_system(object):
def run(self):

    comm_directory = ["net_link", "tsfa_run", "j_link"]
    print "When the system rebooted, some files necessary for"
    print "communicating with the mainland got lost in the directory."
    print "The files were poorly labeled as a result of sloppy"
    print "programming on the staff's part. You must locate the"
    print "the file and contact the rescue team before the dinosaurs"
    print "surround the visitor's center. You were also notified the"
    print "generators were shorting out, and the mainframe will lose"
    print "power at any moment. Which directory will you search in?"
    print "you don't have much time! Option 1: cd /comm_sys/file"
    print "Option 2: cd /comm_sys/dis"
    print "Option 3: cd /comm_sys/comm"

    dir_choice = raw_input("jpark_edwin$ ")

    if dir_choice == "/comm_sys/file" or dir_choice == "/comm_sys/dis":
        print "misc.txt" 
        print "You couldn't locate the file!"
        print "The system lost power and your computer shut down on you!"
        print "You will not be able to reach the mainland until the system"
        print "comes back online, and it will be too late by then."
        return 'death'

    if dir_choice == "/comm_sys/comm":
        comm_directory.append("comm_link")
        print comm_directory
        print "You found the right file and activated it!"
        print "Just in time too, because the computers shut down on you."
        print "The phonelines are radios are still online."
        print "You and the other survivors quickly call the mainlane"
        print "and help is on the way. You all run to the roof and wait"
        print "until the helocopter picks you up. You win!"
a_game = Comm_system()
a_game.run()