如何在Pandas中创建条件文本列？

import pandas as pd
import numpy as np

data = {'Name': ['Alice', 'Bob', 'Charlie', 'David'],
        'Age': [25, 30, 35, 40],
        'Score': [80, 90, 85, 95]}
df = pd.DataFrame(data)

df['Grade'] = np.where(df['Score'] >= 90, 'A', 'B')

print(df)

      Name  Age  Score Grade
0    Alice   25     80     B
1      Bob   30     90     A
2  Charlie   35     85     B
3    David   40     95     A

def get_grade(score):
    if score >= 90:
        return 'A'
    else:
        return 'B'

df['Grade'] = df['Score'].apply(get_grade)

print(df)

      Name  Age  Score Grade
0    Alice   25     80     B
1      Bob   30     90     A
2  Charlie   35     85     B
3    David   40     95     A