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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 auto_thaw(vault_client, opt):
 """Will thaw into a temporary location"""

    icefile = opt.thaw_from
    if not os.path.exists(icefile):
        raise aomi.exceptions.IceFile("%s missing" % icefile)

    thaw(vault_client, icefile, opt)
    return opt