diff --git a/tests/http_strategies.py b/tests/http_strategies.py
index e020e2f..ff7dcdc 100644
--- a/tests/http_strategies.py
+++ b/tests/http_strategies.py
@@ -33,6 +33,7 @@ def http_body():
     """
     Returns random binary body data. Super.
     """
+    alphabet = string.ascii_letters + string.digits + "-._~"
     return strategies.binary(min_size=0, max_size=1500)