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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 get_dip(self):
 """ Return the fault dip as the average dip over the mesh. The average dip is defined as the weighted mean inclination of all the mesh cells. See :meth:`openquake.hazardlib.geo.mesh.RectangularMesh.get_mean_inclination_and_azimuth` :returns: The average dip, in decimal degrees. """

        # uses the same approach as in simple fault surface
        if self.dip is None:
            mesh = self.mesh
            self.dip, self.strike = mesh.get_mean_inclination_and_azimuth()
        return self.dip