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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 interp_color(a, b, f):
 """Interpolate between two colors. Returns: `QColor` object. """

    a_ = (a.redF(), a.greenF(), a.blueF())
    b_ = (b.redF(), b.greenF(), b.blueF())
    a_ = [x * (1 - f) for x in a_]
    b_ = [x * f for x in b_]
    c = [x + y for x, y in zip(a_, b_)]
    return QtGui.QColor.fromRgbF(*c)