Remove dependency on future

I don't think this is needed now that python_requires is >=3.8.

Author: ondras12345

OMPython/OMParser/__init__.py

@@ -32,11 +32,6 @@
  Version: 1.0
 """
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from builtins import int, range
-
 import sys
 
 result = dict()

OMPython/OMTypedParser.py

@@ -1,10 +1,5 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from builtins import int, range
-
 __author__ = "Anand Kalaiarasi Ganeson, ganan642@student.liu.se, 2012-03-19, and Martin Sjölund"
 __license__ = """
  This file is part of OpenModelica.

OMPython/__init__.py

@@ -7,13 +7,7 @@
 omc.sendExpression("command")
 """
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from future.utils import with_metaclass
-from builtins import int, range
 import shutil
-
 import abc
 import csv
 import getpass
@@ -138,7 +132,7 @@ def _get_omc_path(self):
             raise
 
 
-class OMCSessionBase(with_metaclass(abc.ABCMeta, object)):
+class OMCSessionBase(metaclass=abc.ABCMeta):
 
     def __init__(self, readonly=False):
         self.readonly = readonly
@@ -652,7 +646,7 @@ class ModelicaSystemError(Exception):
     pass
 
 
-class ModelicaSystem(object):
+class ModelicaSystem:
     def __init__(self, fileName=None, modelName=None, lmodel=None, commandLineOptions=None,
                  variableFilter=None, customBuildDirectory=None, verbose=True, raiseerrors=False,
                  omhome: str = None, session: OMCSessionBase = None):  # 1

setup.py

@@ -15,7 +15,6 @@
       url='http://openmodelica.org/',
       packages=OMPython_packages,
       install_requires=[
-          'future',
           'numpy',
           'psutil',
           'pyparsing',

tests/test_OMParser.py

@@ -1,10 +1,4 @@
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from builtins import int
-
 from OMPython import OMParser
-
 import unittest
 
 typeCheck = OMParser.typeCheck

tests/test_typedParser.py

@@ -1,10 +1,4 @@
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from builtins import int
-
 from OMPython import OMTypedParser
-
 import unittest
 
 typeCheck = OMTypedParser.parseString