Delete snapshots except those with specific description - python-3.x

Question

I'm trying to delete old AWS snapshots but I need to exclude any with a description value that starts with "Created by CreateImage".
I've tried variations of boto3.resource and boto3.client.
from datetime import datetime, timedelta, timezone
import boto3
client = boto3.client('ec2')
snapshots = client.snapshots.filter(Description!='Created by CreateImage')
def lambda_handler(event, context):
for snapshot in snapshots:
start_time = snapshot.start_time
delete_time = datetime.now(tz=timezone.utc) - timedelta(days=790)
if delete_time > start_time:
snapshot.delete()
print('Snapshot with Id = {} is deleted '.format(snapshot.snapshot_id))
Right now I have about 10 snapshots older than 790 days, 5 with a description that starts with "Created by CreateImage" and 5 that don't. In testing this out I want to delete those snapshots without that description.
the error I get is:
module initialization error: 'EC2' object has no attribute 'snapshots'

Answer 1

Here's a version that works.
Note the use of OwnerIds=['self'] which limits results to only snapshots created by your AWS account. Without this, it will return all publicly-available snapshots created by any AWS account.
from datetime import datetime, timedelta, timezone
import boto3
def lambda_handler(event, context):
delete_time = datetime.now(tz=timezone.utc) - timedelta(days=790)
ec2_resource = boto3.resource('ec2', region_name='ap-southeast-2')
snapshots = ec2_resource.snapshots.filter(OwnerIds=['self'])
for snapshot in snapshots:
if not snapshot.description.startswith('Created by CreateImage') and delete_time > snapshot.start_time:
snapshot.delete()
print('Snapshot with Id = {} is deleted '.format(snapshot.snapshot_id))

Answer 2

You need to use describe_snapshots and properly pass in filters.
Also, the results are going to be a dictionary, not references to the Snapshot class so you need to update the way you pull out the attributes and delete the snapshot.
Something like:
from datetime import datetime, timedelta, timezone
import boto3
client = boto3.client('ec2')
snapshots = client.describe_snapshots(Filters=[
{
'Name': 'description',
'Values': [
'Created by CreateImage',
]
},
])['Snapshots']
def lambda_handler(event, context):
for snapshot in snapshots:
start_time = snapshot['StartTime']
delete_time = datetime.now(tz=timezone.utc) - timedelta(days=790)
if delete_time > start_time:
client.delete_snapshot(SnapshotId=snapshot['SnapshotId'])
print('Snapshot with Id = {} is deleted '.format(snapshot['SnapshotId']))
Reference:
https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/ec2.html#EC2.Client.describe_snapshots