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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 calc_mean(c0, c1=[]):
 """ Calculates the mean of the data."""

    if c1 != []:
        return (numpy.mean(c0, 0) + numpy.mean(c1, 0)) / 2.
    else:
        return numpy.mean(c0, 0)