成绩分布学术QQ图（学术图表）

def solve():
    import pandas as pd
    import matplotlib.pyplot as plt
    import numpy as np
    
    url = 'https://liangdaima.com/static/data/wooldridge/gpa1.csv'
    df = pd.read_csv(url)
    
    from scipy import stats
    plt.rcParams['font.size'] = 12
    sorted_gpa = np.sort(df['colGPA'])
    n = len(sorted_gpa)
    theoretical_quantiles = stats.norm.ppf((np.arange(1, n+1) - 0.5) / n)
    plt.figure(figsize=(8,8))
    plt.scatter(theoretical_quantiles, sorted_gpa, alpha=0.5, color='black', s=30)
    z = np.polyfit(theoretical_quantiles, sorted_gpa, 1)
    plt.plot(theoretical_quantiles, z[0]*theoretical_quantiles + z[1], 'k--', linewidth=2)
    plt.title('GPA正态QQ图', fontsize=14)
    plt.xlabel('理论分位数', fontsize=12)
    plt.ylabel('样本分位数', fontsize=12)
    plt.grid(alpha=0.3)
    plt.tight_layout()
    plt.show()
    return "可视化代码执行完成"