使用pandas dataframe中的城市名称向folium地图添加多个标记

import folium
from geopy.geocoders import Nominatim

map = folium.Map()

def get_coordinates(city):
    geolocator = Nominatim(user_agent="my_app")
    location = geolocator.geocode(city)
    return location.latitude, location.longitude

import pandas as pd

data = {'City': ['北京', '上海', '广州'],
        'Latitude': [0, 0, 0],
        'Longitude': [0, 0, 0]}

df = pd.DataFrame(data)

for index, row in df.iterrows():
    city = row['City']
    latitude, longitude = get_coordinates(city)
    df.at[index, 'Latitude'] = latitude
    df.at[index, 'Longitude'] = longitude

for index, row in df.iterrows():
    city = row['City']
    latitude = row['Latitude']
    longitude = row['Longitude']
    folium.Marker([latitude, longitude], popup=city).add_to(map)

map