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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 getDarkCurrentFunction(exposuretimes, imgs, **kwargs):
    '''
    get dark current function from given images and exposure times
    '''
    exposuretimes, imgs = getDarkCurrentAverages(exposuretimes, imgs)
    offs, ascent, rmse = getLinearityFunction(exposuretimes, imgs, **kwargs)
    return offs, ascent, rmse