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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 numerical_integration(signal, sampling_frequency):
 """ Numerically integrate a signal with it's sampling frequency. :param signal: A 1-dimensional array or list (the signal). :type signal: array :param sampling_frequency: The sampling frequency for the signal. :type sampling_frequency: float :return: The integrated signal. :rtype: numpy.ndarray """

        
    integrate = sum(signal[1:]) / sampling_frequency + sum(signal[:-1])
    integrate /= sampling_frequency * 2
    
    return np.array(integrate)