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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 symmetric_elliot_function( signal, derivative=False ):
 """ A fast approximation of tanh """

    s = 1.0 # steepness
    
    abs_signal = (1 + np.abs(signal * s))
    if derivative:
        return s / abs_signal**2
    else:
        # Return the activation signal
        return (signal * s) / abs_signal