Remove support of Python 2.x

pyproject.toml

@@ -17,10 +17,11 @@ classifiers = [
     "Development Status :: 6 - Mature",
     "Intended Audience :: Developers",
     "License :: OSI Approved :: BSD License",
-    "Programming Language :: Python :: 2.7",
     "Programming Language :: Python :: 3.6",
     "Programming Language :: Python :: 3.7",
     "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
     "Topic :: Software Development :: Libraries :: Python Modules",
     "Topic :: System :: Systems Administration :: Authentication/Directory",
 ]
@@ -32,9 +33,7 @@ include = [
 repository = "https://github.com/pyradius/pyrad"
 
 [tool.poetry.dependencies]
-python = "^2.7 || ^3.6"
-six = "^1.15.0"
-netaddr = "^0.8"
+python = "^3.6"
 
 [tool.poetry.dev-dependencies]
 nose = "^0.10.0b1"

pyrad/client.py

@@ -8,7 +8,6 @@
 import select
 import socket
 import time
-import six
 import struct
 from pyrad import host
 from pyrad import packet
@@ -34,7 +33,7 @@ class Client(host.Host):
     :type timeout: float
     """
     def __init__(self, server, authport=1812, acctport=1813,
-            coaport=3799, secret=six.b(''), dict=None, retries=3, timeout=5):
+            coaport=3799, secret=b'', dict=None, retries=3, timeout=5):
 
         """Constructor.
 

pyrad/client_async.py

@@ -6,7 +6,6 @@
 
 from datetime import datetime
 import asyncio
-import six
 import logging
 import random
 
@@ -175,7 +174,7 @@ class ClientAsync:
     """
     # noinspection PyShadowingBuiltins
     def __init__(self, server, auth_port=1812, acct_port=1813,
-                 coa_port=3799, secret=six.b(''), dict=None,
+                 coa_port=3799, secret=b'', dict=None,
                  loop=None, retries=3, timeout=30,
                  logger_name='pyrad'):
 

pyrad/dictfile.py

@@ -9,7 +9,6 @@
 """
 
 import os
-import six
 
 
 class _Node(object):
@@ -54,10 +53,8 @@ def __init__(self, fil):
         self.__ReadNode(fil)
 
     def __ReadNode(self, fil):
-        node = None
         parentdir = self.__CurDir()
-        if isinstance(fil, six.string_types):
-            fname = None
+        if isinstance(fil, str):
             if os.path.isabs(fil):
                 fname = fil
             else: