Edit Project Path Mappings dialog
The dialog opens when you click 
next to the Path Mappings field in various cases (for example, in the Run/Debug Configuration: Node.js dialog , or when you configure a remote interpreter) .
If in the current run/debug configuration you use an interpreter accessible through SFTP connection or located on a Vagrant instance or in a Docker container, the mappings are automatically retrieved from the corresponding SFTP deployment configuration, Vagrantfile, or Dockerfile, and listed in the dialog. These mappings are read-only.
To add a custom mapping, click
and specify the path in the project and the corresponding path on the remote runtime environment in the Local Path and Remote Path fields respectively. Type the paths manually or click 
and select the relevant files or folders in the dialog that opens.To remove a custom mapping, select it in the list and click
.
Use cases of the path mapping in PyCharm: