Python：将科学数转换为毫秒

我的代码如下所示：

   from pymongo import MongoClient
    client = MongoClient()
    client = MongoClient('localhost', 27017)
    db = client.local
    orderbook = db.orderbook_update.find({'lastUpdated': 1538584913932}).limit(1)
    for order in orderbook:
            timestamp = order['lastUpdated']
            timestamp = timestamp - (timestamp%60000)
            timestamp_target = timestamp + 60000
    orderbook_target = db.orderbook_update.find({'lastUpdated': {'$lt':timestamp_target}}).limit(1)
    def to_millis(time):
      return int(pd.to_datetime(time).value / 1000000)

    print(timestamp_target)
    for orderb in orderbook_target:
        topAsk = orderb['asks'][0][0]
        topBid = orderb['bids'][0][0]

        cOnn= psycopg2.connect("dbname=monty user=postgres host=localhost password=postgres")
        cur = conn.cursor()
        cur.execute("SELECT * FROM binance.zrxeth_aggregated;")
        row = cur.fetchall()
        for r in row:
            ts = to_millis(r[0])
            ts_target = ts- (ts%60000)

            if ts_target == timestamp_target:
                query = 'INSERT INTO binance.zrxeth_aggregated(topBid,topAsk) VALUES (topBid,topAsk)'
                print(query)
                cur. execute(query)
                conn.commit()
    conn.close()

但是最后一个if永远都不是真的，因为ts_target的单位是毫秒：1538589840000，timestamp_target是科学的形式：1.53858492e+12 是否有人对如何将此数字转换为毫秒有任何想法？谢谢！

将其转换为float或int。那可能行得通。

In [153]: a = 1.53858492e+12

In [154]: float(a)
Out[154]: 1538584920000.0

In [155]: int(a)
Out[155]: 1538584920000