Get all File from Subfolder Boto3

I have this code to download all the files from a buckets AWS S3

import os
import boto3

#initiate s3 resource
s3 = boto3.resource('s3')

s3 = boto3.resource(
    's3',
    aws_access_key_id = '__________',
    aws_secret_access_key = '________',
    region_name = '______'
)


# select bucket
my_bucket = s3.Bucket('MainBucket')

# download file into current directory
for s3_object in my_bucket.objects.all():
    # Need to split s3_object.key into path and file name, else it will give error file not found.
    path, filename = os.path.split(s3_object.key)
    my_bucket.download_file(s3_object.key, filename)

Inside that bucket, I have a folder called "pictures"

How can I get the files only in my folder?

My try:

s3.Bucket('MainBucket/pictures')

>Solution :

Inside that bucket, I have a folder called "pictures"

How can I get the files only in my folder?

You can get the files only in the "pictures" folder by providing a prefix:

# select bucket
my_bucket = s3.Bucket('MainBucket')

# download file into current directory
for s3_object in my_bucket.objects.filter(Prefix='pictures/'): <-- FILTER 'PICTURES'
    # Need to split s3_object.key into path and file name, else it will give error file not found.
    path, filename = os.path.split(s3_object.key)
    my_bucket.download_file(s3_object.key, filename)