男女GPA对比柱状图（分组比较）

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)
    
    male_gpa = df[df['male']==1]['colGPA'].mean()
    female_gpa = df[df['male']==0]['colGPA'].mean()
    plt.figure(figsize=(8,6))
    x = np.arange(2)
    plt.bar(x - 0.2, [male_gpa, female_gpa], 0.4, color=['steelblue', 'coral'])
    plt.xticks(x, ['男生', '女生'])
    plt.title('男女大学GPA对比', fontsize=14)
    plt.ylabel('平均GPA', fontsize=12)
    plt.grid(axis='y', alpha=0.3)
    plt.tight_layout()
    plt.show()
    return "可视化代码执行完成"