from zerolife import *

class Instruction():
    def __init__(self, direction, species, coordinates=None):
        '''The optional coordinates parameter is for the pack method.'''
        self.direction = direction
        self.species = species
        self.coordinates = coordinates

    def pack(self, coords):
        '''Packs an instruction object with the coordinates given.'''
        return Instruction(self.direction, self.species,\
        (coords[0]+self.direction[0], coords[1]+self.direction[1]))