settings parameter for project import

Dear all,

I am using the api to import projects from one instance to another. For this I have used the client.prepare_project_import(f) method to generate generate a temprorary handle, which then allows me to call the execute method. My question is, what are the settings that I can pass to this execute method? The documentation for the method indicates that by default the value is settings = {'_':'_'} and I would like to know if I can specify connection mappings, for example.

Thanks for your help