def look_at_obj(self, objecttype):
    # Step 1: Find the object and take it if not already holding
    if self.holding is None or self.name2type(self.holding)!= self.name2type(objecttype):
        # Find the object
        entity = self.find_object(objecttype)
        if entity is None:
            # Explore the environment to find the object
            self.explore()
            return
        else:
            # Go to the object's receptacle and take it
            self.goto(entity.in_on)
            r_entity = self.seen_entitys[entity.in_on]
            if r_entity.openable and not r_entity.isopen:
                self.open_receptacle(r_entity.name)
            self.take(entity.name, entity.in_on)
    
    # Step 2: Find a desklamp
    desklamp = self.find_receptacle('desklamp')
    if desklamp is None:
        # Explore the environment to find a desklamp
        self.explore()
        return
    
    # Step 3: Go to the desklamp and turn it on
    self.goto(desklamp.name)
    self.turn_on(desklamp.name)
    
    # Step 4: Examine the object under the turned-on desklamp
    # Assuming there's a method to examine the object, which is not directly provided in the given code.
    # For the sake of this task, we'll assume examine is implicitly done after turning on the desklamp.
    # If there's a specific examine method, it should be called here.