diff --git a/requirements-dev.txt b/requirements-dev.txt
index 3384c15230..a72eeaa20f 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -6,3 +6,4 @@ pytest-httpbin>=0.0.6
 docutils
 wheel
 pycodestyle
+pyOpenSSL
diff --git a/setup.py b/setup.py
index 3cb04c8b6b..316d23e05c 100644
--- a/setup.py
+++ b/setup.py
@@ -36,7 +36,8 @@ def run_tests(self):
 
 install_requires = [
     'requests>=2.21.0',
-    'Pygments>=2.3.1'
+    'Pygments>=2.3.1',
+    'pyOpenSSL>=19.0.0'
 ]