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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 contour(c, subsample=1, size=10, color='g'):
 """ Draws a contour on the current plot by scattering points. Parameters c : :obj:`autolab_core.Contour` contour to draw subsample : int subsample rate for boundary pixels size : int size of scattered points color : :obj:`str` color of box """

        if not isinstance(c, Contour):
            raise ValueError('Input must be of type Contour')
            
        for i in range(c.num_pixels)[0::subsample]:
            plt.scatter(c.boundary_pixels[i,1], c.boundary_pixels[i,0], s=size, c=color)