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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def make_niche_grid(res_dict, world_size=(60, 60)):
 """ Converts dictionary specifying where resources are to nested lists specifying what sets of resources are where. res_dict - a dictionary in which keys are resources in the environment and values are list of tuples representing the cells they're in. world_size - a tuple indicating the dimensions of the world. Default = 60x60, because that's the default Avida world size Returns a list of lists of sets indicating the set of resources available at each x,y location in the Avida grid. """


    # Initialize array to represent world
    world = initialize_grid(world_size, set())

    # Fill in data on niches present in each cell of the world
    for res in res_dict:
        for cell in res_dict[res]:
            world[cell[1]][cell[0]].add(res)

    return world