Matplotlib-এ হ্যাচ ডেনসিটি (hatch density) কমানো

from matplotlib import pyplot as plt, hatch

plt.rcParams["figure.figsize"] = [7.50, 3.50]
plt.rcParams["figure.autolayout"] = True

class MyHorizontalHatch(hatch.HorizontalHatch):
    def __init__(self, hatch, density):
        char_count = hatch.count('o')
        if char_count > 0:
            self.num_lines = int((1.0 / char_count) * density)
        else:
            self.num_lines = 0
        self.num_vertices = self.num_lines * 2
        super().__init__(hatch, density)

hatch._hatch_types.append(MyHorizontalHatch)

fig = plt.figure()
ax1 = fig.add_subplot(111)
x = [3, 6, 1]
y = [4, 6, 1]
ax1.bar(x, y, color='green', edgecolor='red', hatch="o", lw=1., zorder=0)
plt.show()