[BE] Remove dependency on six and future (pytorch#94709)

Remove the Python 2 and 3 compatibility library [six](https://pypi.org/project/six) and [future](https://pypi.org/project/future) and `torch._six`. We only support Python 3.8+ now. It's time to retire them.

Pull Request resolved: pytorch#94709
Approved by: https://github.com/malfet, https://github.com/Skylion007

.ci/docker/requirements-ci.txt

@@ -36,11 +36,6 @@ flatbuffers==2.0
 #Pinned versions: 2.0
 #test that import:
 
-#future #this breaks linux-bionic-rocm4.5-py3.7
-#Description: compatibility layer between python 2 and python 3
-#Pinned versions:
-#test that import:
-
 hypothesis==5.35.1
 # Pin hypothesis to avoid flakiness: https://github.com/pytorch/pytorch/issues/31136
 #Description: advanced library for generating parametrized tests

.circleci/scripts/binary_linux_test.sh

@@ -82,8 +82,7 @@ if [[ "$PACKAGE_TYPE" == conda ]]; then
       mkl>=2018 \
       ninja \
       typing-extensions \
-      ${PROTOBUF_PACKAGE} \
-      six
+      ${PROTOBUF_PACKAGE}
     if [[ "$DESIRED_CUDA" == 'cpu' ]]; then
       retry conda install -c pytorch -y cpuonly
     else
@@ -100,7 +99,7 @@ if [[ "$PACKAGE_TYPE" == conda ]]; then
   )
 elif [[ "$PACKAGE_TYPE" != libtorch ]]; then
   pip install "\$pkg" --extra-index-url "https://download.pytorch.org/whl/nightly/${DESIRED_CUDA}"
-  retry pip install -q future numpy protobuf typing-extensions six
+  retry pip install -q numpy protobuf typing-extensions
 fi
 if [[ "$PACKAGE_TYPE" == libtorch ]]; then
   pkg="\$(ls /final_pkgs/*-latest.zip)"

.circleci/verbatim-sources/job-specs/job-specs-custom.yml

@@ -626,7 +626,7 @@
             cd ${PROJ_ROOT}/ios/TestApp/benchmark
             mkdir -p ../models
             if [ ${USE_COREML_DELEGATE} == 1 ]; then
-              pip install coremltools==5.0b5 protobuf==3.20.1 six==1.16.0
+              pip install coremltools==5.0b5 protobuf==3.20.1
               python coreml_backend.py
             else
               cd "${PROJ_ROOT}"

.github/ci_commit_pins/xla.txt

@@ -1 +1 @@
-9cbcdb4008c14ad8251c5d4d7723aa616f659edb
+d29eb67c27af0f18d4f487d76b86f43b0a69aade

.github/requirements/conda-env-macOS-ARM64

@@ -5,7 +5,6 @@ cmake=3.22.*
 typing-extensions=4.3.0
 dataclasses=0.8
 pip=22.2.2
-six=1.16.0
 pillow=9.2.0
 pkg-config=0.29.2
 wheel=0.37.1

.github/requirements/conda-env-macOS-X64

@@ -7,7 +7,6 @@ cmake=3.22.*
 typing-extensions=4.3.0
 dataclasses=0.8
 pip=22.2.2
-six=1.16.0
 pillow=9.2.0
 libuv=1.40.0
 pkg-config=0.29.2

.github/requirements/pip-requirements-iOS.txt

@@ -1,4 +1,3 @@
 # iOS simulator requirements
 coremltools==5.0b5
 protobuf==3.20.2
-six==1.16.0

.github/workflows/run_torchbench.yml

@@ -41,7 +41,7 @@ jobs:
           conda activate pr-ci
           conda install -y numpy="${NUMPY_VERSION}" requests ninja pyyaml mkl mkl-include \
                            setuptools cmake=3.22.* typing-extensions boto3 \
-                           six pillow pytest tabulate gitpython git-lfs tqdm psutil
+                           pillow pytest tabulate gitpython git-lfs tqdm psutil
           pip install --pre torch torchvision torchtext -f https://download.pytorch.org/whl/nightly/cu116/torch_nightly.html
       - name: Setup TorchBench branch
         run: |

.lintrunner.toml

@@ -145,7 +145,6 @@ init_command = [
     'expecttest==0.1.3',
     'mypy==0.960',
     'types-requests==2.27.25',
-    'types-six==1.16.15',
     'types-PyYAML==6.0.7',
     'types-tabulate==0.8.8',
     'types-protobuf==3.19.18',

benchmarks/dynamo/Makefile

@@ -28,7 +28,7 @@ build-deps: clone-deps
 	# conda create --name torchdynamo -y python=3.8
 	# conda activate torchdynamo
 	conda install -y astunparse numpy scipy ninja pyyaml mkl mkl-include setuptools cmake \
-		typing-extensions six requests protobuf numba cython scikit-learn
+		typing-extensions requests protobuf numba cython scikit-learn
 	conda install -y -c pytorch magma-cuda116
 	conda install -y -c conda-forge librosa
 	(cd ../../../torchvision && python setup.py clean && python setup.py develop)

caffe2/experiments/python/device_reduce_sum_bench.py

@@ -25,7 +25,6 @@
 import logging
 import os
 
-from six import add_metaclass
 import numpy as np
 
 from caffe2.python import workspace, core
@@ -46,8 +45,7 @@ def __new__(metacls, name, bases, class_dict):
         return cls
 
 
-@add_metaclass(BenchmarkMeta)
-class Benchmark:
+class Benchmark(metaclass=BenchmarkMeta):
 
     def __init__(self):
         self.results = []

docs/caffe2/installation.md

@@ -58,10 +58,6 @@ Note that you might need to uninstall existing Eigen and pybind11 packages due t
 
 ## Python support
 
-To use Caffe2 in Python, you need two libraries, future and six.
-
-    pip install future six
-
 To run the tutorials, download additional source from GitHub.
 
     git clone --recursive https://github.com/caffe2/tutorials.git caffe2_tutorials

docs/cpp/requirements.txt

@@ -6,4 +6,3 @@ docutils==0.16
 -e git+https://github.com/pytorch/pytorch_sphinx_theme.git#egg=pytorch_sphinx_theme
 bs4
 lxml
-six

pyproject.toml

@@ -9,7 +9,6 @@ requires = [
     "setuptools",
     "cmake",
     "typing-extensions",
-    "six",
     "requests",
 ]
 # Use legacy backend to import local packages in setup.py

scripts/build_tegra_x1.sh

@@ -41,10 +41,6 @@ sudo apt-get install \
 # the one provided by apt-get is quite old so we install it via pip
 sudo pip install hypothesis
 
-# Install the six module, which includes Python 2 and 3 compatibility utilities,
-# and is required for Caffe2
-sudo pip install six
-
 # Now, actually build the android target.
 echo "Building caffe2"
 cd $BUILD_ROOT

scripts/build_tizen.sh

@@ -95,10 +95,6 @@ sudo zypper install \
 # Obtain python hypothesis, which Caffe2 uses for unit testing. Note that
 # the one provided by zypper is quite old so we install it via pip
 sudo pip install hypothesis
-
-# Install the six module, which includes Python 2 and 3 compatibility utilities,
-# and is required for Caffe2
-sudo pip install six
 }
 
 caffe2_full_build(){

scripts/model_zoo/update-caffe2-models.py

@@ -6,7 +6,7 @@
 import tarfile
 import tempfile
 
-from six.moves.urllib.request import urlretrieve
+from urllib.request import urlretrieve
 
 from caffe2.python.models.download import downloadFromURLToFile, getURLFromName, deleteDirectory
 

scripts/model_zoo/update-models-from-caffe2.py

@@ -17,7 +17,7 @@
 
 import boto3
 
-from six.moves.urllib.request import urlretrieve
+from urllib.request import urlretrieve
 
 from caffe2.python.models.download import downloadFromURLToFile, getURLFromName, deleteDirectory
 from caffe2.proto import caffe2_pb2

test/distributed/test_store.py

@@ -16,7 +16,6 @@
     sys.exit(0)
 
 import torch.testing._internal.common_utils as common
-from torch._six import string_classes
 from torch.testing._internal.common_distributed import (
     skip_if_win32,
     create_tcp_store
@@ -336,7 +335,7 @@ def __init__(self):
         self.store = {}
 
     def set(self, key, value):
-        if not isinstance(key, string_classes):
+        if not isinstance(key, str):
             raise AssertionError("Expected set to be called with string key")
         if type(value) is not bytes:
             raise AssertionError("Expected set to be called with bytes value")

test/distributions/test_distributions.py

@@ -42,7 +42,7 @@
 # Distributions tests use double as the default dtype
 torch.set_default_dtype(torch.double)
 
-from torch._six import inf, nan
+from torch import inf, nan
 from torch.testing._internal.common_utils import \
     (TestCase, run_tests, set_rng_seed, TEST_WITH_UBSAN, load_tests,
      gradcheck, skipIfTorchDynamo)

test/nn/test_pooling.py

@@ -10,7 +10,7 @@
 import itertools
 import math
 
-from torch._six import inf, nan
+from torch import inf, nan
 import torch
 from torch.testing import make_tensor
 from torch.testing._internal.common_utils import TestCase, run_tests, TEST_WITH_UBSAN, set_default_dtype, \

test/test_autograd.py

@@ -23,7 +23,7 @@
 import torch
 
 from torch import nn
-from torch._six import inf, nan
+from torch import inf, nan
 from torch.autograd.function import once_differentiable
 from torch.autograd.profiler import (profile, record_function, emit_nvtx, emit_itt)
 from torch.autograd.profiler_util import (_format_time, EventList, FunctionEvent, FunctionEventAvg)

test/test_binary_ufuncs.py

@@ -14,7 +14,7 @@
 from functools import partial
 
 import torch.autograd.forward_ad as fwAD
-from torch._six import inf, nan
+from torch import inf, nan
 from torch.testing._internal.common_utils import (
     TestCase,
     slowTest,

test/test_cuda.py

@@ -22,9 +22,9 @@
 import torch
 import torch.cuda
 import torch.cuda.comm as comm
+from torch import inf, nan
 from torch.nn.parallel import scatter_gather
 from torch.utils.checkpoint import checkpoint_sequential
-from torch._six import inf, nan
 from torch.testing._internal.common_utils import TestCase, freeze_rng_state, run_tests, \
     NO_MULTIPROCESSING_SPAWN, skipIfRocm, load_tests, IS_REMOTE_GPU, IS_SANDCASTLE, IS_WINDOWS, \
     slowTest, skipCUDANonDefaultStreamIf, skipCUDAMemoryLeakCheckIf, TEST_WITH_ROCM, TEST_NUMPY, \
@@ -1595,7 +1595,7 @@ def _spawn_test_multinomial_invalid_probs_cuda(self, probs):
             p = subprocess.Popen([sys.executable, '-c', f"""\
 import sys
 import torch
-from torch._six import inf, nan
+from torch import inf, nan
 try:
     with torch.random.fork_rng(devices=[0]):
         torch.multinomial(torch.tensor({probs}).to('cuda'), 2, replacement=True)

test/test_mps.py

@@ -17,7 +17,7 @@
 import torch.nn.functional as F
 import itertools
 from collections import defaultdict
-from torch._six import inf
+from torch import inf
 from torch.nn import Parameter
 from torch.testing._internal import opinfo
 from torch.testing._internal.common_utils import \

test/test_nn.py

@@ -21,7 +21,7 @@
 # NN tests use double as the default dtype
 torch.set_default_dtype(torch.double)
 
-from torch._six import inf, nan
+from torch import inf, nan
 import torch.autograd.forward_ad as fwAD
 import torch.backends.cudnn as cudnn
 import torch.nn as nn

test/test_reductions.py

@@ -11,7 +11,7 @@
 from itertools import product, combinations, permutations
 import warnings
 
-from torch._six import inf, nan
+from torch import inf, nan
 from torch.testing import make_tensor
 from torch.testing._internal.common_dtype import (
     all_types_and_complex_and, get_all_math_dtypes, integral_types, complex_types, floating_types_and,

test/test_shape_ops.py

@@ -8,7 +8,7 @@
 import random
 import warnings
 
-from torch._six import nan
+from torch import nan
 from torch.testing import make_tensor
 from torch.testing._internal.common_utils import (
     TestCase, run_tests, skipIfTorchDynamo, torch_to_numpy_dtype_dict)

test/test_sort_and_select.py

@@ -4,7 +4,7 @@
 import numpy as np
 
 import random
-from torch._six import nan
+from torch import nan
 from itertools import permutations, product
 
 from torch.testing import make_tensor

test/test_torch.py

@@ -24,7 +24,7 @@
 import subprocess
 import weakref
 import sys
-from torch._six import inf, nan, string_classes
+from torch import inf, nan
 from itertools import product, combinations, permutations
 from functools import partial
 from torch import multiprocessing as mp
@@ -8288,7 +8288,7 @@ def _test_namespace(ns, *skips):
                 ns_name = ns.__name__
             skip_regexes = []
             for r in skips:
-                if isinstance(r, string_classes):
+                if isinstance(r, str):
                     skip_regexes.append(re.compile('^{}$'.format(re.escape(r))))
                 else:
                     skip_regexes.append(r)

test/test_unary_ufuncs.py

@@ -8,7 +8,7 @@
 import random
 import unittest
 
-from torch._six import inf, nan
+from torch import inf, nan
 from torch.testing._internal.common_utils import (
     TestCase,
     run_tests,

torch/_C/_VariableFunctions.pyi.in

@@ -1,8 +1,7 @@
 # ${generated_comment}
 
-from torch import Tensor, Generator, strided, memory_format, contiguous_format, strided
+from torch import Tensor, Generator, strided, memory_format, contiguous_format, strided, inf
 from typing import List, Tuple, Optional, Union, Any, ContextManager, Callable, overload, Iterator, NamedTuple, Sequence, Literal, TypeVar
-from torch._six import inf
 
 from torch.types import _int, _float, _bool, Number, _dtype, _device, _qscheme, _size, _layout, SymInt, Device
 import torch