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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 mean(l, ignore_nan=False, empty=0):
 """ nanmean compatible with generators. """

    l = iter(l)
    if ignore_nan:
        l = ifilterfalse(np.isnan, l)
    try:
        n = 1
        acc = next(l)
    except StopIteration:
        if empty == 'raise':
            raise ValueError('Empty mean')
        return empty
    for n, v in enumerate(l, 2):
        acc += v
    if n == 1:
        return acc
    return acc / n