Fix a str/unicode concatenation problem.
Fix a str/unicode concatenation problem.

WillianPaiva/1flow,1flow/1flow,1flow/1flow,1flow/1flow,WillianPaiva/1flow,1flow/1flow,WillianPaiva/1flow,1flow/1flow,WillianPaiva/1flow,WillianPaiva/1flow