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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 log_sum_exp_ab(a, b):
 """log_sum_exp for two scalars. Parameters a, b: float Returns ------- c: float c = log(e^a + e^b) """

    if a > b:
        return a + np.log(1. + np.exp(b - a))
    else:
        return b + np.log(1. + np.exp(a - b))