How to make two markers share the same label in the legend using matplotlib?

Question

What I want is like this:

What I get is this:

Answer 1

You can do this by plotting data without any label and then adding the label separately:

from matplotlib import pyplot as plt
from numpy import random

xs = range(10)
data = random.rand(10, 2)    
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
kwargs = {'color': 'r', 'linewidth': 2, 'linestyle': '--'}

ax.plot(xs, data, **kwargs)
ax.plot([], [], label='Model', **kwargs)
ax.legend()
plt.show()