diff --git a/stix2/__init__.py b/stix2/__init__.py
index bf48a48..215030f 100644
--- a/stix2/__init__.py
+++ b/stix2/__init__.py
@@ -194,6 +194,7 @@ class Relationship(_STIXBase):
         'target_ref',
     ]
 
+    # Explicitly define the first three kwargs to make readable Relationship declarations.
     def __init__(self, source_ref=None, relationship_type=None, target_ref=None,
                  **kwargs):
         # TODO:
diff --git a/stix2/test/test_stix2.py b/stix2/test/test_stix2.py
index 591be64..82a7607 100644
--- a/stix2/test/test_stix2.py
+++ b/stix2/test/test_stix2.py
@@ -37,7 +37,6 @@ MALWARE_KWARGS = dict(
     name="Cryptolocker",
 )
 
-
 # Minimum required args for a Relationship instance
 RELATIONSHIP_KWARGS = dict(
     relationship_type="indicates",