Poisson Distribution in Python

import numpy as np
import matplotlib.pyplot as plt
import seaborn as sns
from scipy.stats import poisson

# If we have know that between 4:30pm and 4:45pm each weekday an average of 3.6 customers enter any given checkout line. What is the probability that exactly 7 customers enter your line between 4:30pm and 4:45pm?
mu = 3.6
exact_seven = 7
poisson.pmf(exact_seven, mu)

seven_or_less = poisson.cdf(7,mu)
seven_or_less

seven_or_most = 1 - poisson.cdf(6,mu)
seven_or_most

poisson.mean(3.6)

poisson.var(3.6)

poisson.std(3.6)


# Visualization
sns.set_theme(style = 'darkgrid')
x_ax = np.arange(0,11)
y_ax = poisson.pmf(x_ax, 3.6)
sns.barplot(x = x_ax, y = y_ax)
plt.show()

y_ax = poisson.cdf(x_ax, 3.6)
sns.barplot(x = x_ax, y = y_ax)
plt.show()