Interesting python behavior : newb here

[zeros]

I just started learning python a few days ago. I'm noticing some behavior that I don't understand in one of my scripts:

#!/usr/bin/python

import main # this is main

class ReadFile():
	result = []
	
	def make_moldata(self):
		data = open('fixed.txt','r')
		universe = data.readlines()
		data.close()
		datum = []
		target = float()
		for line in universe:
			if line == '\n':
				self.result.append(main.MolData(targ=datum[0], descs=datum[1:-1]))
				datum = []
			else:
				datum.append(line.strip())
		return self.result
		
class MolData():
	descriptors = []
	target = float()
	
	def __init__(self, targ, descs):
		self.descriptors = list(descs)
		self.target = float(targ)
	
	def __getitem__(self, index):
		return self.descriptors[index]
		
	def __setitem__(self, index, value):
		self.descriptors[index] = value
	
	def __len__(self):
		return len(self.descriptors)
	
	def __repr__(self):
		s = self.descriptors.__repr__() + ' : ' + self.target.__repr__()
		return s
	
	def gettarget(self):
		return self.target
		
	def get(self,index):
		return self.__getitem__(index)
	
class OrderedData():
	unordered = []
	ordered = []
	
	def __init__(self,data=[]):
		self.unordered = data
		
	def order(self):
		self.ordered = self.do_it()
		return self.ordered
		
	def do_it(self):           # incomplete
		pass

def run():
	print "Running!"

	universe = main.ReadFile().make_moldata()
	ordered = main.OrderedData(universe)
	ordered.order()

	print "Bye!"
	
run()

When I run ./main.py I get

Running!
Bye!
Running!
Bye!

but importing main in an interactive session only runs it once. Does anyone know why this is happening? Also, any critiques? Am I doing anything that screams my pythonic newbness? Suggestions for improvement?
Thanks.

[zeros]

In case someone else runs into a similar problem, I found my error: it was the `import main` statement. It was causing the module to import and run itself before getting to the `run()` statement at the bottom. I had added it because I was having problems getting a module to run various functions implemented in it, but since the definition of `run()` is above it's call, in this case it works out.