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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 sleuthify_sailfish(sailfish_dir):
 """ if installed, use wasabi to create abundance.h5 output for use with sleuth """

    if not R_package_path("wasabi"):
        return None
    else:
        rscript = Rscript_cmd()
        cmd = """{rscript} --no-environ -e 'library("wasabi"); prepare_fish_for_sleuth(c("{sailfish_dir}"))'"""
        do.run(cmd.format(**locals()), "Converting Sailfish to Sleuth format.")
    return os.path.join(sailfish_dir, "abundance.h5")