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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 ls():
 # pylint:disable=C0103 """ List all installed Quilt data packages """

    for pkg_dir in PackageStore.find_store_dirs():
        print("%s" % pkg_dir)
        packages = PackageStore(pkg_dir).ls_packages()
        for package, tag, pkghash in sorted(packages):
            print("{0:30} {1:20} {2}".format(package, tag, pkghash))