from matplotlib import pyplot as plt
import pandas as pd

orders = pd.read_csv('orders.csv')

customer_amount = orders.groupby('customer_id').price.sum().reset_index()

print (customer_amount.head())

plt.hist(customer_amount.price.values, range=(0, 200), bins=40)
plt.xlabel('Total Spent')
plt.ylabel("Number of Customers")
plt.title('Customer Expenditure Over 6 Months')

plt.show()