plots with rotation in text

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
#reading the data

test_data = pd.read_csv('recall.csv')

print(test_data)

#print(test_data['Sensor'])
y_pos = np.arange(len(test_data['Sensors']))
plt.bar(y_pos,test_data['Value'], align='center', alpha=1,color='black')
plt.xticks(y_pos, test_data['Sensors'],rotation=45)
plt.ylim(.85,1.0)
plt.show()