diff --git a/vyper/builtin_functions/functions.py b/vyper/builtin_functions/functions.py
index 42d49322fd..776b3162fb 100644
--- a/vyper/builtin_functions/functions.py
+++ b/vyper/builtin_functions/functions.py
@@ -266,7 +266,7 @@ def build_LLL(self, expr, args, kwargs, context):
             # if we are slicing msg.data, the length should
             # be a constant, since msg.data can be of dynamic length
             # we can't use it's length as the maxlen
-            assert isinstance(length.value, int) # sanity check
+            assert isinstance(length.value, int)  # sanity check
             sub_typ_maxlen = length.value
         else:
             sub_typ_maxlen = sub.typ.maxlen
diff --git a/vyper/evm/opcodes.py b/vyper/evm/opcodes.py
index a1e1664c35..6cf908cb8f 100644
--- a/vyper/evm/opcodes.py
+++ b/vyper/evm/opcodes.py
@@ -195,7 +195,7 @@
     "ASSERT": (None, 1, 0, 85),
     "ASSERT_UNREACHABLE": (None, 1, 0, 17),
     "PASS": (None, 0, 0, 0),
-    "DUMMY": (None, 0, 1, 0), # tell LLL that no, there really is a stack item here
+    "DUMMY": (None, 0, 1, 0),  # tell LLL that no, there really is a stack item here
     "BREAK": (None, 0, 0, 20),
     "CONTINUE": (None, 0, 0, 20),
     "SHA3_32": (None, 1, 1, 72),
diff --git a/vyper/ovm/transpile_lll.py b/vyper/ovm/transpile_lll.py
index 5e6b3e5e9f..8a7fa245a9 100644
--- a/vyper/ovm/transpile_lll.py
+++ b/vyper/ovm/transpile_lll.py
@@ -657,7 +657,9 @@ def generate_label(opcode):
             + [lll for lll in reversed(rewritten_args)]
             + [["goto", subroutine.subroutine_label()]]
             + [["label", label]]
-            + ["dummy"] if subroutine.evm_returns else ["pass"]
+            + ["dummy"]
+            if subroutine.evm_returns
+            else ["pass"]
         )
 
     lll_ret = [lll_node.value] + rewritten_args