'Create a label for this repository.
:param str name: (required), name to give to the label
:param str color: (required), value of the color to assign to the
label, e.g., \'#fafafa\' or \'fafafa\' (the latter is what is sent)
:returns: :class:`Label <github3.issues.label.Label>` if successful,
else None'

@requires_auth
def create_label(self, name, color):

    json = None
    if (name and color):
        data = {u'name': name, u'color': color.strip(u'#')}
        url = self._build_url(u'labels', base_url=self._api)
        json = self._json(self._post(url, data=data), 201)
    return self._instance_or_null(Label, json)
