确定样本量均值

def solve():
    import pandas as pd
    import numpy as np
    import matplotlib.pyplot as plt
    from scipy.stats import norm
    url = '____'
    df = pd.read_csv(____)
    sig = df['____'].std()
    n = int(np.ceil((norm.ppf(____)*sig/____)**____))
    print(____)
    e_vals = np.linspace(____, ____, ____)
    n_vals = [(norm.ppf(____)*sig/e)**____ for e in e_vals]
    plt.plot(____)
    plt.axvline(____, color='____', ls='____', label='____')
    plt.axhline(____)
    plt.xlabel(____); plt.ylabel(____); plt.title(____); plt.legend()
    plt.tight_layout(); plt.show()