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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 s3_read(source, profile_name=None):
 """ Read a file from an S3 source. Parameters source : str Path starting with s3://, e.g. 's3://bucket-name/key/foo.bar' profile_name : str, optional AWS profile Returns ------- content : bytes Raises ------ botocore.exceptions.NoCredentialsError Botocore is not able to find your credentials. Either specify profile_name or add the environment variables AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY and AWS_SESSION_TOKEN. See https://boto3.readthedocs.io/en/latest/guide/configuration.html """

    session = boto3.Session(profile_name=profile_name)
    s3 = session.client('s3')
    bucket_name, key = _s3_path_split(source)
    s3_object = s3.get_object(Bucket=bucket_name, Key=key)
    body = s3_object['Body']
    return body.read()