Go through the following documentation
http://boto3.readthedocs.io/en/latest/guide/migrations3.html
Creating the Connection
Boto 3 has both low-level clients and higher-level resources. For Amazon S3, the higher-level resources are the most similar to Boto 2.x's s3 module:
Boto 2.x import boto
s3_connection = boto.connect_s3() Boto 3
import boto3
s3 = boto3.resource('s3') Creating a Bucket
Creating a bucket in Boto 2 and Boto 3 is very similar, except that in Boto 3 all action parameters must be passed via keyword arguments and a bucket configuration must be specified manually:
Boto 2.x
s3_connection.create_bucket('mybucket')
s3_connection.create_bucket('mybucket', location=Location.USWest) Boto 3
s3.create_bucket(Bucket='mybucket')
s3.create_bucket(Bucket='mybucket', CreateBucketConfiguration={ 'LocationConstraint': 'us-west-1'}) Storing Data
Storing data from a file, stream, or string is easy:
Boto 2.x
from boto.s3.key import Key
key = Key('hello.txt')
key.set_contents_from_file('/tmp/hello.txt') Boto 3
s3.Object('mybucket', 'hello.txt').put(Body=open('/tmp/hello.txt', 'rb'))