'Get the pull request indicated by ``number``.
:param int number: (required), number of the pull request.
:returns: :class:`PullRequest <github3.pulls.PullRequest>`'

def pull_request(self, number):

    json = None
    if (int(number) > 0):
        url = self._build_url(u'pulls', str(number), base_url=self._api)
        json = self._json(self._get(url), 200)
    return self._instance_or_null(PullRequest, json)
