def write_the_species_tree(annotated_species_tree, output_file):
    """
    this function writes the species tree to file

    args:
        annotated_species_tree : a string of annotated species tree in .newick format
        output_file : a file name to write to
    output:
        a file containing the annotated species tree 
    """
    with open(output_file, "w") as out:
        out.write(annotated_species_tree)

    print("wrote the annotated species besttree to "+output_file)
    return output_file