绘制收益率分布与正态拟合

import pandas as pd
import numpy as np
from scipy import stats
import matplotlib
matplotlib.use(____)
import matplotlib.pyplot as plt

def solve():
    url = '____'
    df = pd.read_excel(____)
    r = np.log(____).diff().dropna()
    mu, std = stats.norm.fit(____)
    plt.figure(figsize=(____, ____))
    plt.hist(____)
    x = np.linspace(r.min(), r.max(), ____)
    plt.plot(x, stats.norm.pdf(____), '____', linewidth=____)
    plt.title(____)
    plt.tight_layout()
    plt.show()
    print(____)