Declare Python 3.7 as supported
diff --git a/setup.py b/setup.py
index 242ba9b..5fccadb 100755
--- a/setup.py
+++ b/setup.py
@@ -46,6 +46,7 @@
               'Programming Language :: Python :: 3.4',
               'Programming Language :: Python :: 3.5',
               'Programming Language :: Python :: 3.6',
+              'Programming Language :: Python :: 3.7',
               'Programming Language :: Python :: Implementation :: CPython',
               'Programming Language :: Python :: Implementation :: PyPy',
               'Topic :: Security :: Cryptography',