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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 plot_fiber_slice(self, plane=None, index=None, fig=None):
 r""" Plot one slice from the fiber image Parameters plane : array_like List of 3 values, [x,y,z], 2 must be zero and the other must be between zero and one representing the fraction of the domain to slice along the non-zero axis index : array_like similar to plane but instead of the fraction an index of the image is used """

        if hasattr(self, '_fiber_image') is False:
            logger.warning('This method only works when a fiber image exists')
            return
        slice_image = self._get_fiber_slice(plane, index)
        if slice_image is not None:
            if fig is None:
                plt.figure()
            plt.imshow(slice_image.T, cmap='Greys', origin='lower',
                       interpolation='nearest')

        return fig