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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_curve(values, weights=None):
 """ Compute the mean by using numpy.average on the first axis. """

    if weights is None:
        weights = [1. / len(values)] * len(values)
    if not isinstance(values, numpy.ndarray):
        values = numpy.array(values)
    return numpy.average(values, axis=0, weights=weights)