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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 nm2lt7(short_nm: float, long_nm: float, step_cminv: float = 20) -> Tuple[float, float, float]: """converts wavelength in nm to cm^-1 minimum meaningful step is 20, but 5 is minimum before crashing lowtran short: shortest wavelength e.g. 200 nm long: longest wavelength e.g. 30000 nm step: step size in cm^-1 e.g. 20 output in cm^-1 """

    short = 1e7 / short_nm
    long = 1e7 / long_nm

    N = int(np.ceil((short-long) / step_cminv)) + 1  # yes, ceil

    return short, long, N