Update Python classifiers for PyPI

Author: mdmintz

setup.py

@@ -101,7 +101,6 @@
         "Operating System :: POSIX :: Linux",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",