def get_git_tag(self, sha):
assert isinstance(sha, (str, unicode)), sha<EOL>headers, data = self._requester.requestJsonAndCheck(<EOL>"<STR_LIT:GET>",<EOL>self.url + "<STR_LIT>" + sha<EOL>)<EOL>return github.GitTag.GitTag(self._requester, headers, data, completed=True)<EOL>
:calls: `GET /repos/:owner/:repo/git/tags/:sha <http://developer.github.com/v3/git/tags>`_
:param sha: string
:rtype: :class:`github.GitTag.GitTag`