Matplotlib multicolor legend

multicolor_legend.py

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.legend_handler import HandlerLineCollection, HandlerNpoints, HandlerBase, HandlerLine2D, HandlerTuple

plot1 = plt.plot([3, 2, 1], [1, 2, 3])
plot2 = plt.plot([1, 2, 3], [3, 2, 1])

multi_color_line = tuple(
    [plt.plot([0, 0, 0], color=plt.get_cmap('rainbow')(v)[:3])[0] for v in np.linspace(0.0, 1.0, 5)])
l = plt.legend([multi_color_line, plot1[0], plot2[0]], ['Multiple color 0', 'Color1', 'Color2'],
               handler_map={tuple: HandlerTuple(ndivide=None, pad=0)})

plt.show()