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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 recommended_overlap(name, nfft=None):
 """Returns the recommended fractional overlap for the given window If ``nfft`` is given, the return is in samples Parameters name : `str` the name of the window you are using nfft : `int`, optional the length of the window Returns ------- rov : `float`, `int` the recommended overlap (ROV) for the given window, in samples if ``nfft` is given (`int`), otherwise fractional (`float`) Examples -------- 0.5 85 """

    try:
        name = canonical_name(name)
    except KeyError as exc:
        raise ValueError(str(exc))
    try:
        rov = ROV[name]
    except KeyError:
        raise ValueError("no recommended overlap for %r window" % name)
    if nfft:
        return int(ceil(nfft * rov))
    return rov