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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 defineGeometry(self):
 """Set the 3D geometry of the cell."""

        self.soma.L = 18.8
        self.soma.diam = 18.8
        self.soma.Ra = 123.0

        self.dend.L = 200.0
        self.dend.diam = 1.0
        self.dend.Ra = 100.0