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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 freeze(dest_dir, opt):
 """Iterates over the Secretfile looking for secrets to freeze"""

    tmp_dir = ensure_tmpdir()
    dest_prefix = "%s/dest" % tmp_dir
    ensure_dir(dest_dir)
    ensure_dir(dest_prefix)
    config = get_secretfile(opt)
    Context.load(config, opt) \
           .freeze(dest_prefix)
    zip_filename = freeze_archive(tmp_dir, dest_prefix)
    ice_file = freeze_encrypt(dest_dir, zip_filename, config, opt)
    shutil.rmtree(tmp_dir)
    LOG.debug("Generated file is %s", ice_file)