import matplotlib.pyplot as plt
import json
movies= json.load(open('movies.json',encoding='utf-8'))
rating=[]
durations=[]
for m in movies:
    rating.append(m['rating'])
    durations.append(m['duration'])

plt.figure(figsize=(8,5))
plt.scatter(durations,rating,color='red',alpha=0.6)
plt.title("时长与评分关系散点图")
plt.xlabel('duration')
plt.ylabel('rating')
plt.savefig('q4_2_scatter.png',dpi=150)