def get_package_url(cls, package, session=None, silent=False):
        response = get("{}/packages/{}".format(cls.bower_base_uri, package))
        return response.json().get("url", None)
def get_revision(cls, location, rev=None):
        if rev is None:
            rev = 'HEAD'
        current_rev = cls.run_command(
            ['rev-parse', rev],
            show_stdout=False,
            stdout_only=True,
            cwd=location,
        )
        return current_rev.strip()