def create_git_ref(self, ref, sha):
assert isinstance(ref, (str, unicode)), ref<EOL>assert isinstance(sha, (str, unicode)), sha<EOL>post_parameters = {<EOL>"<STR_LIT>": ref,<EOL>"<STR_LIT>": sha,<EOL>}<EOL>headers, data = self._requester.requestJsonAndCheck(<EOL>"<STR_LIT:POST>",<EOL>self.url + "<STR_LIT>",<EOL>input=post_parameters<EOL>)<EOL>return github.GitRef.GitRef(self._requester, headers, data, completed=True)<EOL>
:calls: `POST /repos/:owner/:repo/git/refs <http://developer.github.com/v3/git/refs>`_
:param ref: string
:param sha: string
:rtype: :class:`github.GitRef.GitRef`