Remove unicode /Python3 checks

[arcturusannamalai]

Open-Tamil migrated to Python3 earlier this year. We nolonger need code like,

PYTHON3 = version > '3' del version

and

if not isinstance(uyirmei_char, PYTHON3 and str or str): raise ValueError("Passed input letter '%s' must be unicode, \ not just string" % uyirmei_char)

[arcturusannamalai]

thanks @HariharanUmapathi