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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def put_file(buffer, modified_file):
 """ write the buffer to modified_file. modified_file should be in the format 's3://bucketname/path/to/file.txt' """

    import mimetypes
    import boto3
    file_type, _ = mimetypes.guess_type(modified_file)

    s3 = boto3.resource('s3')
    bucket_name, object_key = _parse_s3_file(modified_file)
    extra_args = {
        'ACL': 'public-read',
        'ContentType': file_type
    }
    bucket = s3.Bucket(bucket_name)
    logger.info("Uploading {0} to {1}".format(object_key, bucket_name))
    bucket.upload_fileobj(buffer, object_key, ExtraArgs=extra_args)