diff --git a/src/qibotn/backends/quimb.py b/src/qibotn/backends/quimb.py
index 756d994..331c6f7 100644
--- a/src/qibotn/backends/quimb.py
+++ b/src/qibotn/backends/quimb.py
@@ -314,7 +314,6 @@ if not __name__ == "__main__":
             The corresponding Quimb operator.
         """
         op_str = op_str.lower()
-        # breakpoint()
         op = qu.pauli(op_str[0])
         for c in op_str[1:]:
             op = op & qu.pauli(c)