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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 get_imr_length(approx, **kwds):
 """Call through to pnutils to obtain IMR waveform durations """

    m1 = float(kwds['mass1'])
    m2 = float(kwds['mass2'])
    s1z = float(kwds['spin1z'])
    s2z = float(kwds['spin2z'])
    f_low = float(kwds['f_lower'])
    # 10% margin of error is incorporated in the pnutils function
    return pnutils.get_imr_duration(m1, m2, s1z, s2z, f_low, approximant=approx)