How to plot all trees in booster and visualize its structure

#1

use xgboost.plot_tree can only plot one tree, default 0.
you can use code blow to plot all trees:

import math
import matplotlib.pyplot as plt

dump_list = bst.get_dump()
num_trees = len(dump_list)

cols = 4
rows = math.ceil(num_trees / cols)
fig, axs = plt.subplots(rows, cols, figsize=(22, 60), sharex=False, sharey=False)

for i in range(num_trees):
    row = int(i / cols)
    col = int(i % cols)
    ax = axs[row, col]
    plot_tree(bst, num_trees=i, ax=ax)

but I have not figout how construct those trees: which are boost trees and bagging trees?
the global layout is missing?