what is object name and file name in botos3 code example

Example 1: boto3 upload file to s3

import boto3
s3 = boto3.resource('s3')
s3.meta.client.upload_file('/tmp/hello.txt', 'mybucket', 'hello.txt')

Example 2: upload_file boto3 headers

import boto3
s3 = boto3.resource('s3')
s3.meta.client.upload_file('source_file_name.html', 'my.bucket.com', 'aws_file_name.html', ExtraArgs={'ContentType': "application/json", 'ACL': "public-read"} )