matplotlib event handling to interact with objects on the canvas

I'm using this code to draw a plot of connected points and to drag the points freely on the plot. I just need to change the polygon fill color from Blue to White. Please advise how to do so.

import numpy as np
from matplotlib.lines import Line2D
from matplotlib.artist import Artist
from matplotlib.mlab import dist_point_to_segment

class PolygonInteractor:

    showverts = True
    epsilon = 5  # max pixel distance to count as a vertex hit

    def __init__(self, ax, poly):
        if poly.figure is None:
            raise RuntimeError('You must first add the polygon to a figure or canvas before defining the interactor')
        self.ax = ax
        canvas = poly.figure.canvas
        self.poly = poly

        x, y = zip(*self.poly.xy)
        self.line = Line2D(x, y, marker='o', markerfacecolor='r', animated=True)
        self.ax.add_line(self.line)
        #self._update_line(poly)

        cid = self.poly.add_callback(self.poly_changed)
        self._ind = None # the active vert

        canvas.mpl_connect('draw_event', self.draw_callback)
        canvas.mpl_connect('button_press_event', self.button_press_callback)
        canvas.mpl_connect('key_press_event', self.key_press_callback)
        canvas.mpl_connect('button_release_event', self.button_release_callback)
        canvas.mpl_connect('motion_notify_event', self.motion_notify_callback)
        self.canvas = canvas


    def draw_callback(self, event):
        self.background = self.canvas.copy_from_bbox(self.ax.bbox)
        self.ax.draw_artist(self.poly)
        self.ax.draw_artist(self.line)
        self.canvas.blit(self.ax.bbox)

    def poly_changed(self, poly):
        'this method is called whenever the polygon object is called'
        # only copy the artist props to the line (except visibility)
        vis = self.line.get_visible()
        Artist.update_from(self.line, poly)
        self.line.set_visible(vis)  # don't use the poly visibility state


    def get_ind_under_point(self, event):
        'get the index of the vertex under point if within epsilon tolerance'

        # display coords
        xy = np.asarray(self.poly.xy)
        xyt = self.poly.get_transform().transform(xy)
        xt, yt = xyt[:, 0], xyt[:, 1]
        d = np.sqrt((xt-event.x)**2 + (yt-event.y)**2)
        indseq = np.nonzero(np.equal(d, np.amin(d)))[0]
        ind = indseq[0]

        if d[ind]>=self.epsilon:
            ind = None

        return ind

    def button_press_callback(self, event):
        'whenever a mouse button is pressed'
        if not self.showverts: return
        if event.inaxes==None: return
        if event.button != 1: return
        self._ind = self.get_ind_under_point(event)

    def button_release_callback(self, event):
        'whenever a mouse button is released'
        if not self.showverts: return
        if event.button != 1: return
        self._ind = None

    def key_press_callback(self, event):
        'whenever a key is pressed'
        if not event.inaxes: return
        if event.key=='t':
            self.showverts = not self.showverts
            self.line.set_visible(self.showverts)
            if not self.showverts: self._ind = None
        elif event.key=='d':
            ind = self.get_ind_under_point(event)
            if ind is not None:
                self.poly.xy = [tup for i,tup in enumerate(self.poly.xy) if i!=ind]
                self.line.set_data(zip(*self.poly.xy))
        elif event.key=='i':
            xys = self.poly.get_transform().transform(self.poly.xy)
            p = event.x, event.y # display coords
            for i in range(len(xys)-1):
                s0 = xys[i]
                s1 = xys[i+1]
                d = dist_point_to_segment(p, s0, s1)
                if d<=self.epsilon:
                    self.poly.xy = np.array(
                        list(self.poly.xy[:i]) +
                        [(event.xdata, event.ydata)] +
                        list(self.poly.xy[i:]))
                    self.line.set_data(zip(*self.poly.xy))
                    break


        self.canvas.draw()

    def motion_notify_callback(self, event):
        'on mouse movement'
        if not self.showverts: return
        if self._ind is None: return
        if event.inaxes is None: return
        if event.button != 1: return
        x,y = event.xdata, event.ydata

        self.poly.xy[self._ind] = x,y
        self.line.set_data(zip(*self.poly.xy))

        self.canvas.restore_region(self.background)
        self.ax.draw_artist(self.poly)
        self.ax.draw_artist(self.line)
        self.canvas.blit(self.ax.bbox)


if __name__ == '__main__':
    import matplotlib.pyplot as plt
    from matplotlib.patches import Polygon

    theta = np.arange(0, 2*np.pi, 0.1)
    r = 1.5

    xs = r*np.cos(theta)
    ys = r*np.sin(theta)

    poly = Polygon(list(zip(xs, ys)), animated=True)

    fig, ax = plt.subplots()
    ax.add_patch(poly)
    p = PolygonInteractor(ax, poly)

    #ax.add_line(p.line)
    ax.set_title('Click and drag a point to move it')
    ax.set_xlim((-2,2))
    ax.set_ylim((-2,2))
    plt.show()