提取GBDT特征重要性前15名

def solve():
    from pyodide.http import open_url
    from io import StringIO
    loans_featured_csv = open_url(____).read()
    import pandas as pd
    from sklearn.ensemble import GradientBoostingClassifier
    from sklearn.model_selection import train_test_split
    from io import StringIO
    df = pd.read_csv(StringIO(____))
    num_cols=[c for c in df.select_dtypes(____).columns if c not in ['____','____'] and not c.endswith(____)]
    X=df[num_cols].fillna(____); y=df['____']
    X_tr,X_te,y_tr,y_te=train_test_split(____)
    gb=GradientBoostingClassifier(____)
    gb.fit(____)
    imp=pd.DataFrame({'____':num_cols,'____':gb.feature_importances_.round(____)})
    print(imp.nlargest(____,'____').to_string(____))