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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 zip_bundle(tag=True):
 """Create zip file upload bundles. @param tag Use git tag instead of hash? """

    #rev = get_rev(tag)
    rev = __version__

    print("Cleaning old build files.")
    clean()

    local("mkdir -p build")

    print("Bundling new files.")
    with lcd("sphinx_bootstrap_theme/bootstrap"):
        local("zip -r ../../build/bootstrap.zip .")

    dest = os.path.abspath(os.path.join(DL_DIR, rev))
    with lcd("build"):
        local("mkdir -p %s" % dest)
        local("cp bootstrap.zip %s" % dest)

        print("Verifying contents.")
        local("unzip -l bootstrap.zip")