SPC均值控制图

def solve():
    import pandas as pd
    import numpy as np
    import matplotlib.pyplot as plt
    url = '____'
    df = pd.read_csv(____)
    sample_cols = [f'____' for i in range(____,____)]
    df['____'] = df[sample_cols].mean(____)
    overall_mean = df['____'].mean()
    R = df[sample_cols].max(____) - df[sample_cols].min(____)
    R_bar = R.mean()
    A2 = ____
    UCL = overall_mean + A2*R_bar
    LCL = overall_mean - A2*R_bar
    print(____)
    plt.figure(figsize=(____,____))
    plt.plot(____)
    plt.axhline(____)
    plt.axhline(____)
    plt.axhline(____)
    plt.xlabel(____); plt.ylabel(____); plt.title(____)
    plt.legend(); plt.tight_layout(); plt.show()