如何将带有对象的字典转换为geoJson？

import json

def dict_to_geojson(obj_dict):
    # 确定对象的几何类型和属性
    geometry_type = obj_dict.get('geometry_type', '')
    properties = obj_dict.get('properties', {})

    # 创建GeoJSON模板
    geojson = {
        'type': 'Feature',
        'geometry': {
            'type': geometry_type,
            'coordinates': []
        },
        'properties': properties
    }

    # 将对象的坐标信息添加到GeoJSON模板中
    coordinates = obj_dict.get('coordinates', [])
    if geometry_type == 'Point':
        geojson['geometry']['coordinates'] = coordinates
    elif geometry_type == 'LineString' or geometry_type == 'Polygon':
        geojson['geometry']['coordinates'] = [coordinates]

    return json.dumps(geojson)

# 示例对象字典
object_dict = {
    'geometry_type': 'Point',
    'coordinates': [120.0, 30.0],
    'properties': {
        'name': 'Location A',
        'category': 'Point of Interest'
    }
}

# 转换为GeoJSON
geojson_str = dict_to_geojson(object_dict)
print(geojson_str)