diff --git a/bitten/bitten.py b/bitten/bitten.py
index 9210824..c641502 100644
--- a/bitten/bitten.py
+++ b/bitten/bitten.py
@@ -650,7 +650,9 @@ def _bite(
             lower = lower if lower.ndim else _repeat(lower)
             upper = upper if upper.ndim else _repeat(upper)
             new = [(l, u) for _, l, u in zip(range(hyper.dims), lower, upper)]
-            assert len(new) == hyper.dims, f"length of bounds must equal number of dimensions"
+            assert (
+                len(new) == hyper.dims
+            ), f"length of bounds must equal number of dimensions"
             linear_bounds += new
         elif isinstance(hyper, Bound):
             linear_bounds.append(hyper.bounds)