Index: spacemap.py
==================================================================
--- spacemap.py
+++ spacemap.py
@@ -1,6 +1,6 @@
-class SpaceMap:
+class SpaceMap(object):
 	''' Here we have:
 	__bottom - minimum space address possible;
 	__top - maximum space address possible;
 	__pairs - internal list of ranges;
 	__walk_list - internal list of keys.'''
@@ -27,14 +27,14 @@
 
 	def __set(self, name, value):
 		'''Internal function to add ranges without folding. Also checks for range correctness.'''
 		if type(name) != int or type(value) != int or name >= value:
 			return(False)
-		if not self.__bottom == None:
+		if self.__bottom != None:
 			if name < self.__bottom or value < self.__bottom:
 				return(False)
-		if not self.__top == None:
+		if self.__top != None:
 			if name >= self.__top or value >= self.__top:
 				return(False)
 		self.__pairs[name] = value
 		return True
 
@@ -82,11 +82,11 @@
 		'''Returns the inner dict with ranges.'''
 		return(repr(self.__pairs))
 
 	def __and__(self, other):
 		'''Returns new space map with ranges that appears both in A and B.'''
-		if not type(other) == SpaceMap:
+		if type(other) != SpaceMap:
 			return(False)
 		new = {}
 		self.rewind()
 		other.rewind()
 		my_pair = self.pop()
@@ -179,11 +179,11 @@
 		other.clear()
 		return(SpaceMap(new, self.__bottom, self.__top))
 
 	def __sub__(self, other):
 		'''Returns new space map with ranges in A not covered by B.'''
-		if not type(other) == SpaceMap:
+		if type(other) != SpaceMap:
 			return(False)
 		new = {}
 		self.rewind()
 		other.rewind()
 		my_pair = self.pop()

Index: test.py
==================================================================
--- test.py
+++ test.py
@@ -1,5 +1,9 @@
+from __future__ import print_function, unicode_literals
+
+from spacemap import SpaceMap
+
 def test():
 	def check(desc, correct, result):
 		if correct == result:
 			print('PASSED:', desc, '==' , result, '==', correct)
 		else: