def save(self, filename=None):
        filename = Path(filename) if filename is not None else self.filename
        with filename.open("w") as f:
            f.write(self.yaml)
def test_git_branch():
    """ Test checkout w/ Branch """
    git_checkout(git_url='https://github.com/voltgrid/voltgrid-pie.git', git_branch='master', git_tag=None)