I want to rename the number 1->picture (32) with python not the number 2->picture with the (3745), can someone help me with that ?
The item you tagged as (1) is the objects data block and can be changed via python with
bpy.data.objects['3745'].data.name = 'newName'
Instead of referring to an object directly by name you can access the active object's data block with
bpy.context.object.data.name = 'newName'