Python如何创建一个新的列来测量城市的接近度？

import pandas as pd
from geopy.distance import geodesic

data = {'City': ['City A', 'City B', 'City C'],
        'Latitude': [latitude_A, latitude_B, latitude_C],
        'Longitude': [longitude_A, longitude_B, longitude_C]}
df = pd.DataFrame(data)

def calculate_distance(row):
    city_A = (row['Latitude'], row['Longitude'])
    city_B = (latitude_target, longitude_target)
    return geodesic(city_A, city_B).km

df['Distance'] = df.apply(calculate_distance, axis=1)

city_A_distance = df.loc[df['City'] == 'City A', 'Distance'].values[0]