PyMongo checking if entry is already in array - pymongo

Question

I want to have an array of IPs that went to x webpage and have them in an array. However right now everytime an IP connects it gets added, if multiple people connect multiple times there'll be many duplicates.
Currently I'm just using
query = {"_id": paste_id, "ip": {"$ne": real_ip}
collection.update_one(query, {"$push": {"ip": ip}})
but that (logically) just pushes the entry into the array, what'd be a way to check if ip is already in the array?

Answer 1

UPDATED ANSWER
The updated code you posted is checking for real_ip and then inserting ip; so you're not checking the item your actually updating.
My original answer below still stands as the correct approach; however this complete example demonstrates attempting to insert the real_ip 5 times and it shows the value is only inserted once:
from pymongo import MongoClient
collection = MongoClient()['mydatabase'].collection
result = collection.insert_one({'ip': []})
paste_id = result.inserted_id
real_ip = '1.2.3.4'
for i in range(5):
query = {"_id": paste_id, "ip": {"$ne": real_ip}}
collection.update_one(query, {"$push": {"ip": real_ip}})
print(list(collection.find()))
prints:
[{'_id': ObjectId('5feefdb862e2ed3ea952a035'), 'ip': ['1.2.3.4']}]
ORIGINAL ANSWER
Add a check that the IP is not already in the ip array, e.g.
query = {'ip': {'$ne': ip}}