import pymongo
import csv
import json
import sys
import importlib
importlib.reload(sys)
import xlwt
from pymongo import MongoClient该导的先导进来
mongo_url = "172.28.9.62:1234"
# mongodb服务的地址和端口号url参数
client = pymongo.MongoClient(mongo_url)获取client
DATABASE = "test"
#连接到数据库test
db = client[DATABASE]
db.collection_names()
显示子集名称COLLECTION = "microblogs"
db_coll = db[COLLECTION ]子数据集
queryArgs = {'geo':{'$ne':None}}
projectionFields = {'geo':True,'text':True,'user_id':True,'created_at':True}
searchRes = db_coll.find(queryArgs, projection = projectionFields)接下来是查找操作，find（条件，返回值）
写入excel和txt特辑：