diff -r 39f349391898 -r 82131be5258e mercurial/dispatch.py
--- a/mercurial/dispatch.py	Wed Feb 14 11:53:04 2024 -0500
+++ b/mercurial/dispatch.py	Wed Feb 14 15:23:59 2024 -0500
@@ -413,7 +413,7 @@
                     # debugging has been requested
                     with demandimport.deactivated():
                         try:
-                            debugmod = __import__(debugger)
+                            debugmod = __import__(pycompat.sysstr(debugger))
                         except ImportError:
                             pass  # Leave debugmod = pdb