Add missing docstring for `expected_body` parameter

Signed-off-by: Sean Quah <seanq@element.io>

1 files changed, 2 insertions, 0 deletions

diff --git a/tests/http/server/_base.py b/tests/http/server/_base.py

index dc82085581..02b20b2cc8 100644
--- a/tests/http/server/_base.py
+++ b/tests/http/server/_base.py
@@ -48,6 +48,8 @@ class EndpointCancellationTestHelperMixin(unittest.TestCase):
             expect_cancellation: `True` if request processing is expected to be
                 cancelled, `False` if the request should run to completion.
             expected_body: The expected response for the request.
+            expected_code: The expected status code for the request. Defaults to `200`
+                or `499` depending on `expect_cancellation`.
         """
         # Determine the expected status code.
         if expected_code is None: