def compute_psi(alpha, market_params, maturity_time_years, characteristic_function, variable):
    """
    Calculate characteristic function dependent quantity in the integrand term.
    Args:
        alpha: Regularization parameter.
        market_params: The market parameters.
        maturity_time_years: Measured in years relative to today, today being zero.
        characteristic_function: The characteristic function of the density.
        variable: The argument.

    Returns:
        Intermediate quantity in the integrand term in the Fourier transform.

    """
    temp1 = complex(variable, -1.0 * (alpha + 1.0))
    temp2 = characteristic_function(market_params, maturity_time_years, temp1)
    temp3 = 1.0 / complex((alpha * (alpha + 1.0)) - (variable * variable),
                          ((2.0 * alpha) + 1.0) * variable)
    temp4 = temp2 * temp3
    return temp4