Update Doc/using/cmdline.rst

Co-authored-by: Adam Turner <[email protected]>

Author: noahbkim

Doc/using/cmdline.rst

@@ -990,7 +990,7 @@ conflict.
 
 .. envvar:: PYTHONPROFILEIMPORTTIME
 
-   If this environment variable is set to a non-empty string, Python will show
+   If this environment variable is set to ``1``, Python will show
    how long each import takes. If set to ``2``, Python will include output for
    imported modules that have already been loaded.
    This is equivalent to setting the :option:`-X` ``importtime`` option.