import numpy as np
from sklearn.datasets import load_iris
import pandas as pd
import matplotlib.pyplot as plt

iris = load_iris()
iris_pd=pd.DataFrame(data=np.c_[iris['data'], iris['target']], columns=iris['feature_names'] + ['target'])

x1 = np.array(iris_pd['sepal length (cm)'])
x2 = np.array(iris_pd['sepal width (cm)'])
x3 = np.array(iris_pd['petal length (cm)'])
x4 = np.array(iris_pd['petal length (cm)'])

plt.boxplot([x1,x2,x3,x4], tick_labels = ['Sepal Length', 'Sepal Width', 'Petal Length', 'Petal Width'])
#plt.set_ylabel('')
plt.show()