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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 _merge_two_curves(curve1: Curve, curve2: Curve, qmin, qmax, qsep, use_additive_constant=False):
 """Merge two scattering curves :param curve1: the first curve (longer distance) :type curve1: sastool.classes.curve.GeneralCurve :param curve2: the second curve (shorter distance) :type curve2: sastool.classes.curve.GeneralCurve :param qmin: lower bound of the interval for determining the scaling factor :type qmin: float :param qmax: upper bound of the interval for determining the scaling factor :type qmax: float :param qsep: separating (tailoring) point for the merge :type qsep: float :return: merged_curve, factor, background, stat :rtype tuple of a sastool.classes2.curve.Curve and a float """

    curve1=curve1.sanitize()
    curve2=curve2.sanitize()
    if len(curve1.trim(qmin, qmax)) > len(curve2.trim(qmin, qmax)):
        curve2_interp = curve2.trim(qmin, qmax)
        curve1_interp = curve1.interpolate(curve2_interp.q)
    else:
        curve1_interp = curve1.trim(qmin, qmax)
        curve2_interp = curve2.interpolate(curve1_interp.q)
    if use_additive_constant:
        bg_init = 0
    else:
        bg_init = FixedParameter(0)
    factor, bg, stat = nonlinear_odr(curve2_interp.Intensity, curve1_interp.Intensity,
                                     curve2_interp.Error, curve1_interp.Error,
                                     lambda x, factor, bg: x * factor + bg, [1.0, bg_init])
    return Curve.merge(curve1 - bg, curve2 * factor, qsep), factor, bg, stat