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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 diff_a_thing(thing, opt):
 """Handle the diff action for a single thing. It may be a Vault backend implementation or it may be a Vault data resource"""

    changed = thing.diff()
    if changed == ADD:
        print("%s %s" % (maybe_colored("+", "green", opt), str(thing)))
    elif changed == DEL:
        print("%s %s" % (maybe_colored("-", "red", opt), str(thing)))
    elif changed == CHANGED:
        print("%s %s" % (maybe_colored("~", "yellow", opt), str(thing)))
    elif changed == OVERWRITE:
        print("%s %s" % (maybe_colored("+", "yellow", opt), str(thing)))
    elif changed == CONFLICT:
        print("%s %s" % (maybe_colored("!", "red", opt), str(thing)))

    if changed != OVERWRITE and changed != NOOP:
        maybe_details(thing, opt)