[Python] How to bind a pick event callback directly to an artisti in matplotlib

I'm drawing 2 lines into a figure and I want to draw a vertical line when clicking the lines. What I want is the callback "on_pick_line1" being called when clicking on line "y1" and "on_pick_line2" when clicking on line y2.

All examples in the documentation show how to bind a callback to the event "on_pick" of the canvas but it does not know which line has been clicked.

I wrote the Pick_dispatcher class that routes the "on_pick" events to my callbacks. The solution works but, in my opinion is complicated.

Is there any way to bind the callback "on_pick_line1" directly to line "y1" and so on?

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt


class Pick_dispatcher():
"""Pick callbacks register themselfs into the dispatcher, then they'll get called"""

def __init__(self):
self.callbacks = {}

def register_callback(self, artist, func):
self.callbacks[artist] = func

def unregister_callback(self, artist, func):
del self.callbacks[artist]

def __call__(self, event):
artist = event.artist
print("Dispatcher calling ", artist.get_label())
self.callbacks[artist](event)



def on_pick_line1(event):
artist = event.artist
i_sel = event.ind # list of indexes selected vertices
i_med = i_sel[len(i_sel) // 2] # index of median vertex
x = artist.get_xdata()[i_med] # median vertex
ax = artist.axes
ax.axvline(x, ls='--', lw=1, color='blue')
artist.get_figure().canvas.draw_idle()



def on_pick_line2(event):
artist = event.artist
i_sel = event.ind
i_med = i_sel[len(i_sel) // 2]
x = artist.get_xdata()[i_med]
ax = artist.axes
ax.axvline(x, ls='--', lw=1, color='red')
artist.get_figure().canvas.draw_idle()




if __name__ == "__main__":


# Sample traces
x = np.array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11])
y1 = np.array([0, 0, 0, 1, 2, 3, 4, 5, 6, 6, 6, 6])
y2 = np.array([0, 0, 1, 2, 3, 4, 5, 5, 5, 5, 5, 5])

# Prepare plot
fig, ax = plt.subplots()

pick_dispatcher = Pick_dispatcher()

tolerance = 5 # points
f, = ax.plot(x, y1, marker=".", ms=2, lw=1, label='y1', picker=True, pickradius=tolerance)
pick_dispatcher.register_callback(f, on_pick_line1)

g, = ax.plot(x, y2, marker=".", ms=2, lw=1, label='y2', picker=True, pickradius=tolerance)
pick_dispatcher.register_callback(g, on_pick_line2)

plt.legend()

fig.canvas.callbacks.connect('pick_event', pick_dispatcher)
plt.show()

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