In Jupyter Notebook or JupyterLab, there isn't a built-in "Replace" interface with a direct keyboard shortcut like in some text editors. However, you can use the Find and Replace feature with the following steps:

Jupyter Notebook (Classic)

• Find and Replace can be accessed via the Edit menu:
  • Edit > Find and Replace (or use Ctrl + F to open Find, then click the "Replace" button in the dialog).

JupyterLab

• Find and Replace is available in the Edit menu:
  • Edit > Find (Ctrl + F), then click the Replace button in the Find bar.

Keyboard Shortcut (JupyterLab)

• There is no default shortcut for Replace, but you can:
  1. Open the Find bar with Ctrl + F.
  2. Click the Replace button in the Find bar to expand it.

If you frequently use this feature, you can customize keyboard shortcuts in JupyterLab by editing the Advanced Settings Editor under Settings > Advanced Settings Editor.