py3: Update setup.py

Require Python 3.6+ in setup.py

setup.py

@@ -21,24 +21,13 @@ requirements = [
     "wcwidth==0.2.5",
     "ida-settings==2.1.0",
     "viv-utils==0.6.0",
+    "halo==0.0.31",
+    "networkx==2.5.1",
+    "ruamel.yaml==0.17.0",
+    "vivisect==1.0.1",
+    "smda==1.5.13",
 ]
 
-if sys.version_info >= (3, 0):
-    # py3
-    requirements.append("halo==0.0.31")
-    requirements.append("networkx==2.5.1")
-    requirements.append("ruamel.yaml==0.17.0")
-    requirements.append("vivisect==1.0.1")
-    requirements.append("smda==1.5.13")
-else:
-    # py2
-    requirements.append("enum34==1.1.6")  # v1.1.6 is needed by halo 0.0.30 / spinners 0.0.24
-    requirements.append("halo==0.0.30")  # halo==0.0.30 is the last version to support py2.7
-    requirements.append("vivisect==0.2.1")
-    requirements.append("networkx==2.2")  # v2.2 is last version supported by Python 2.7
-    requirements.append("ruamel.yaml==0.16.13")  # last version tested with Python 2.7
-    requirements.append("backports.functools-lru-cache==1.6.1")
-
 # this sets __version__
 # via: http://stackoverflow.com/a/7071358/87207
 # and: http://stackoverflow.com/a/2073599/87207
@@ -77,13 +66,13 @@ setuptools.setup(
     install_requires=requirements,
     extras_require={
         "dev": [
-            "pytest==4.6.11",  # TODO: Change to 6.2.3 when removing py2
+            "pytest==6.2.3",
             "pytest-sugar==0.9.4",
             "pytest-instafail==0.4.2",
             "pytest-cov==2.11.1",
             "pycodestyle==2.7.0",
-            "black==20.8b1 ; python_version>'3.0'",
-            "isort==4.3.21",  # TODO: Change to 5.8.0 when removing py2
+            "black==20.8b1",
+            "isort==5.8.0",
         ]
     },
     zip_safe=False,
@@ -94,8 +83,8 @@ setuptools.setup(
         "Intended Audience :: Information Technology",
         "License :: OSI Approved :: Apache Software License",
         "Natural Language :: English",
-        "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
         "Topic :: Security",
     ],
+    python_requires=">=3.6",
 )