Select the active object ? with python i just want to select this object, the suzanne with the active origin in red,'is is she active or just the last selected?

i dont know the code, and i dont know also how to find this kind of code, ive been searching for two hours... any tips how to find the desired action within blender in this kind of cases?

thanks
You can usually retrieve the active object with: bpy.context.active_object or bpy.context.object
If you need to take the view layer into account: bpy.context.view_layer.objects.active
Chances are your view layer is already set, but if the view layer needs to be set, you can first do: bpy.context.window.view_layer = view_layer
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To make sure the active object is also a selected object, you can do this:
import bpy
my_object = bpy.context.view_layer.objects.active # assign variable
my_object.select_set(True) # select the object

Setting an object as active is a similar process. See this answer to learn about that.
Many operations require both an active object and at least one additional selected object.