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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 _remap_key(key):
 """ Change key into correct casing if we know the parameter """

    if key in KNOWN_PARAMS:
        return key
    if key.lower() in known_params:
        return KNOWN_PARAMS[known_params.index(key.lower())]
    return key