def pick_and_place(self, objecttype, receptacletype):
    # First, ensure the agent is not already holding an object
    if self.holding is not None:
        # If the agent is holding something, it needs to put it down before picking up a new object
        # Find a suitable receptacle to place the currently held object
        r_types = self.find_canbe_contained(self.name2type(self.holding))
        if r_types is not None:
            for r_type in r_types:
                r_entitys = self.find_receptacles(r_type)
                if r_entitys is not None:
                    for r_entity in r_entitys:
                        self.goto(r_entity.name)
                        if r_entity.openable and not r_entity.isopen:
                            self.open_receptacle(r_entity.name)
                        self.put(self.holding, r_entity.name)
                        break
                    break
        else:
            # If no suitable receptacle is found, the agent cannot proceed
            return

    # Now, attempt to pick up the object of the given type
    entity = self.find_object(objecttype)
    if entity is None:
        # If the object is not found, explore the environment to find it
        self.explore()
        return
    else:
        # If the object is found, go to its 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)

    # Now, place the object in the specified receptacle
    r_entity = self.find_receptacle(receptacletype)
    if r_entity is None:
        # If the receptacle is not found, explore the environment to find it
        self.explore()
        return
    else:
        # If the receptacle is found, go to it and place the object
        self.goto(r_entity.name)
        if r_entity.openable and not r_entity.isopen:
            self.open_receptacle(r_entity.name)
        self.put(self.holding, r_entity.name)