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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 getDampingIntegral(self):
 """Calculate integral of damping terms of hamiltonian using rectangular method. """

        reservoir = self.getReservoir()
        density = self.getDensity()
        length = self.model.getSpatialStep()

        if self.solution.ndim == 1:
            nodes = self.model.getNumberOfNodes()
            radius = linspace(0, nodes * self.model.getSpatialStep(), nodes)
            integral = 2 * pi * sum((reservoir - 1.0) * density * radius * length)
        elif self.solution.ndim == 2:
            area = length ** 2
            integral = sum(sum((reservoir - 1.0) * density * area))

        return integral