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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_if_greater_than_zero(vals):
 """ Calculate mean over numerical values, ignoring values less than zero. E.g. used for mean time over coincident triggers when timestamps are set to -1 for ifos not included in the coincidence. Parameters vals: iterator of numerical values values to be mean averaged Returns ------- mean: float The mean of the values in the original vector which are greater than zero num_above_zero: int The number of entries in the vector which are above zero """

    vals = numpy.array(vals)
    above_zero = vals > 0
    return vals[above_zero].mean(), above_zero.sum()