How to add (or annotate) value labels (or frequencies) on a matplotlib "histogram" chart

I want to add frequency labels to the histogram generated using plt.hist.

Here is the data :

np.random.seed(30)
d = np.random.randint(1, 101, size = 25)
print(sorted(d))

I looked up other questions on stackoverflow like : Adding value labels on a matplotlib bar chart and their answers, but apparantly, the objects returnded by plt.plot(kind='bar') are different than than those returned by plt.hist, and I got errors while using the 'get_height' or 'get width' functions, as suggested in some of the answers for bar plot.

Similarly, couldn't find the solution by going through the matplotlib documentation on histograms. got this error

Here is how I managed it. If anyone has some suggestions to improve my answer, (specifically the for loop and using n=0, n=n+1, I think there must be a better way to write the for loop without having to use n in this manner), I'd welcome it.

# import base packages
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt

# generate data
np.random.seed(30)
d = np.random.randint(1, 101, size = 25)
print(sorted(d))

# generate histogram

# a histogram returns 3 objects : n (i.e. frequncies), bins, patches
freq, bins, patches = plt.hist(d, edgecolor='white', label='d', bins=range(1,101,10))

# x coordinate for labels
bin_centers = np.diff(bins)*0.5 + bins[:-1]

n = 0
for fr, x, patch in zip(freq, bin_centers, patches):
  height = int(freq[n])
  plt.annotate("{}".format(height),
               xy = (x, height),             # top left corner of the histogram bar
               xytext = (0,0.2),             # offsetting label position above its bar
               textcoords = "offset points", # Offset (in points) from the *xy* value
               ha = 'center', va = 'bottom'
               )
  n = n+1

plt.legend()
plt.show;