Bpy.ops.mesh.seperate is not working. [SOLVED]

I wrote very simple script

def execute(self, context):
    cursor = bpy.context.scene.cursor
    obj = bpy.context.active_object
    bpy.ops.object.mode_set( mode = 'OBJECT' )
    faceId = obj.closest_point_on_mesh(cursor.location)[3]

    if faceId != -1:
        obj.data.polygons[ faceId ].select = True

    bpy.ops.object.mode_set( mode = 'EDIT' )
    return {'FINISHED'}  

As you can see, scrupt selects a face, extends selections to other faces and detaches the selected faces. Nothing like that happens.
I have such a error

bpy.ops.mesh.seperate error, could not be found
ret = op_call(self.idname_py(), None, kw)

Maybe some of you know what is wrong? Becouse I don’t have idea.

Greets and thx for help.

you’ve spelled it ‘seperate’, which is a common misspelling of the word ‘separate’

What a stupid mistake. I’m ashamed…

don’t be, it’s a common mistake :slight_smile: