Remove several mentions of Python 2 (#190)

* Remove several mentions of Python 2
Not all of them are removed with these changes, because I am not sure
how best to remove some of them, e.g. in the file debian/control

* Remove uses of six package

Author: jafingerhut

README.md

@@ -41,7 +41,7 @@ More information about Black, you find at
 
 The following software is required to run PTF:
 
- * Python 2.7 or 3.x
+ * Python 3.x
  * six 1.16.0
  * Scapy 2.4.5 (unless you provide another packet manipulation module)
  * pypcap (optional - VLAN tests will fail without this)

ptf_nn/ptf_nn_agent.py

@@ -305,10 +305,7 @@ def forward(self, p, port):
         msg = struct.pack("<iii{}s".format(len(p)), self.MSG_TYPE_PACKET_OUT,
                           port, len(p), p)
         # because nnpy expects unicode when using str
-        if sys.version_info[0] == 2:
-            msg = list(bytes(msg))
-        else:
-            msg = bytearray(msg)
+        msg = bytearray(msg)
 
         self.socket.send(msg)
 

requirements.txt

@@ -1 +0,0 @@
-six==1.16.0

setup.cfg

@@ -19,7 +19,7 @@ package_dir=
 packages = find:
 scripts = ptf, ptf_nn/ptf_nn_agent.py
 platforms = any
-python_requires = >=2.7, >=3
+python_requires = >=3
 setup_requires =
     setuptools_scm
 install_requires = file: requirements.txt

src/ptf/dataplane.py

@@ -32,7 +32,7 @@
 from . import mask
 from . import packet
 from .pcap_writer import PcapWriter
-from six import StringIO
+from io import StringIO
 
 try:
     import nnpy
@@ -321,10 +321,7 @@ def send(self, port_number, packet):
             packet,
         )
         # because nnpy expects unicode when using str
-        if sys.version_info[0] == 2:
-            msg = list(msg)
-        else:
-            msg = bytearray(msg)
+        msg = bytearray(msg)
         self.socket.send(msg)
         # nnpy does not return the number of bytes sent
         return len(packet)

src/ptf/mask.py

@@ -1,7 +1,7 @@
 from __future__ import print_function
 import warnings
 
-from six import StringIO
+from io import StringIO
 import sys
 from . import packet
 

src/ptf/testutils.py

@@ -11,7 +11,7 @@
 import ptf.parse
 import ptf.ptfutils
 import codecs
-from six import StringIO
+from io import StringIO
 
 global skipped_test_count
 skipped_test_count = 0
@@ -3179,7 +3179,7 @@ def ptf_ports(num=None):
 
 
 def port_to_tuple(port):
-    if type(port) is int or (sys.version_info[0] == 2 and type(port) is int):
+    if type(port) is int:
         return 0, port
     if type(port) is tuple:
         return port