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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_delta_c(c200):
 """Calculate characteristic overdensity from concentration. Parameters c200 : ndarray or float Cluster concentration parameter. Returns ndarray or float Cluster characteristic overdensity, of same type as c200. """

    top = (200. / 3.) * c200**3.
    bottom = np.log(1. + c200) - (c200 / (1. + c200))
    return (top / bottom)