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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 volume(self, vol, clim=None, method='mip', threshold=None, cmap='grays'):
 """Show a 3D volume Parameters vol : ndarray Volume to render. clim : tuple of two floats | None The contrast limits. The values in the volume are mapped to black and white corresponding to these values. Default maps between min and max. method : {'mip', 'iso', 'translucent', 'additive'} The render style to use. See corresponding docs for details. Default 'mip'. threshold : float The threshold to use for the isosurafce render style. By default the mean of the given volume is used. cmap : str The colormap to use. Returns ------- volume : instance of Volume The volume visualization. See also -------- Volume """

        self._configure_3d()
        volume = scene.Volume(vol, clim, method, threshold, cmap=cmap)
        self.view.add(volume)
        self.view.camera.set_range()
        return volume