def pick_and_place(self, objecttype, receptacletype):
    # Step 1: Pick up the object of the given objecttype
    if self.holding is None or self.name2type(self.holding) != self.name2type(objecttype):
        # Find the object with the given objecttype
        entity = self.find_object(objecttype)
        if entity is None:
            # If the object is not found, find receptacle types that can contain the object
            r_types = self.find_canbe_contained(objecttype)
            if r_types is None:
                # If no receptacle types are found, explore the environment
                self.explore()
                return  # After exploring, return for the next decision-making
            else:
                # Iterate through the receptacle types to find the object
                for r_type in r_types:
                    r_entitys = self.find_receptacles(r_type)
                    if r_entitys is None:
                        continue  # If no receptacles of this type are found, continue to the next type
                    for r_entity in r_entitys:
                        # Go to the receptacle and check if it's open
                        self.goto(r_entity.name)
                        if r_entity.openable and not r_entity.isopen:
                            # If the receptacle is closed, open it
                            self.open_receptacle(r_entity.name)
                            return  # After opening, return for the next decision-making
        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:
                # If the receptacle is closed, open it
                self.open_receptacle(r_entity.name)
            self.take(entity.name, entity.in_on)
            return  # After taking the object, return for the next decision-making

    # Step 2: Place the object into a receptacle of the given receptacletype
    if self.holding is not None and self.name2type(self.holding) == self.name2type(objecttype):
        # Find a receptacle of the given receptacletype
        r_entity = self.find_receptacle(receptacletype)
        if r_entity is None:
            # If no receptacle is found, explore the environment
            self.explore()
            return  # After exploring, return for the next decision-making
        else:
            # Go to the receptacle and place the object
            self.goto(r_entity.name)
            if r_entity.openable and not r_entity.isopen:
                # If the receptacle is closed, open it
                self.open_receptacle(r_entity.name)
            self.put(self.holding, r_entity.name)
            return  # After placing the object, return for the next decision-making