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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 interpret_maskval(paramDict):
 """

    # interpret user specified final_maskval value to use for initializing
    # output SCI array...
    if 'maskval' not in paramDict:
        return 0
    maskval = paramDict['maskval']
    if maskval is None:
        maskval = np.nan
    else:
        maskval = float(maskval) # just to be clear and absolutely sure...
    return maskval