import matplotlib.pyplot as plt

# Assuming you have a list of categories and their values
categories = ['Category1', 'Category2', 'Category3']
values = [20, 35, 30]

plt.bar(categories, values)

# Loop to add values on each bar
for i in range(len(values)):
    plt.text(x = i, y = values[i]+0.5, s = values[i], ha = 'center')

plt.show()