drop support for Python 3.6

Author: graingert

setup.py

@@ -40,13 +40,12 @@
         'Topic :: Software Development :: Testing',
         'Topic :: Software Development :: Libraries',
         'License :: OSI Approved :: MIT License',
-        'Programming Language :: Python :: 2',
-        'Programming Language :: Python :: 2.6',
-        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.4',
-        'Programming Language :: Python :: 3.5',
-        'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3 :: Only',
+        'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
     ],
 
     # What does your project relate to?
@@ -55,6 +54,7 @@
     include_package_data = True, # include files listed in MANIFEST.in
     install_requires = ['httpbin','six'],
     extras_require = {"test": ["requests", "pytest"]},
+    python_requires = ">=3.7",
 
     # the following makes a plugin available to pytest
     entry_points = {