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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 _decode_config(conf_str):
 """ Decode string to configuration dict. Only values defined in settings._ALLOWED_MERGES can be redefined. """

    conf_str = conf_str.strip()

    # convert "tttff" -> [True, True, True, False, False]
    conf = map(
        lambda x: True if x.upper() == "T" else False,
        list(conf_str)
    )

    return dict(zip(settings._ALLOWED_MERGES, conf))