Plot the filter

        Parameters
        ----------
        fig: bokeh.plotting.figure (optional)
            A figure to plot on
        draw: bool
            Draw the figure, else return it

        Returns
        -------
        bokeh.plotting.figure
            The filter figure

def plot(self, fig=None, draw=True):
        """
        Plot the filter

        Parameters
        ----------
        fig: bokeh.plotting.figure (optional)
            A figure to plot on
        draw: bool
            Draw the figure, else return it

        Returns
        -------
        bokeh.plotting.figure
            The filter figure
        """
        COLORS = color_gen('Category10')

        # Make the figure
        if fig is None:
            xlab = 'Wavelength [{}]'.format(self.wave_units)
            ylab = 'Throughput'
            title = self.filterID
            fig = figure(title=title, x_axis_label=xlab, y_axis_label=ylab)

        # Plot the raw curve
        fig.line((self.raw[0]*q.AA).to(self.wave_units), self.raw[1],
                 alpha=0.1, line_width=8, color='black')

        # Plot each with bin centers
        for x, y in self.rsr:
            fig.line(x, y, color=next(COLORS), line_width=2)
        fig.circle(*self.centers, size=8, color='black')

        if draw:
            show(fig)
        else:
            return fig