Made the "base64encode" method version-agnostic

[tatyushev-ms]

Made the "base64encode" method return the same result type (a sequence of bytes) whatever the python version it's run on

[coveralls]

Pull Request Test Coverage Report for Build 74

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 51.443%

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Totals
Change from base Build 71:	0.0%
Covered Lines:	731
Relevant Lines:	1421

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💛 - Coveralls

[idlesign]

Thank you. Merged.